Mac mini Ende 2012 Logic Board austauschen

I think it depends, I have seen some that are very difficult to open and some super easy. But I see them everyday. I wish there was a tool that fit in the holes.

When seating the bottom RAM chip you may have to apply a little extra side force to get it to seat properly. I put in the new RAM and just got a beeping sound upon starting. I then put the old RAM back in and got the same result.

Here is the solution I found on the Apple discussion board.

"Take a small flat head screwdriver and after you put the memory in slot 0, put the screwdriver between the top of the mac mini and the memory then turn the screwdriver a little to exert pressure on the memory into the slot. Do it on both sides of the memory."

This worked for me.

I remember this when I was changing my memory ... I realized (after opening) that more you push, more force it take to open the cover. As you push down you force the cover "to rub" the casing and possibly other things inside. If you "lightly" hold the cover it comes right off ... Remember: less is more! :-)

Have fun!

We found it hard to use the thumbs but if you put the casing on a carpet and one person is holding the case while the other is using his palm of one hand to turn the cover it comes off quite smoothly and without much downward pressure.

If you're upgrading to an SSD, before you even take this first step, I'd recommend putting the SSD into an external drive case, using USB and format the SSD first before trying to swap your existing hard drive or implementing a fusion drive. The external drive case will come in handy later so you can use the old drive as extra storage anyhow.

Once that SSD is internal, the Mac errors out during the formatting process. Once it was formatted externally, then installed inside the Mac again, there was no problem.

The first time I did this it hurt! The second time my mac mini 2012 had been running so was warm. VERY EASY WHEN WARM. No fun when cool!

Forget about those 2 circle indents. if you consider the 2 marked dots (open and close) as position 12 o’clock, place your thumbs at 11 and 1 o’clock on the outer rim of the cover and rotate from that position.

No way was I getting the back off. So I made a tool. Took a large wrench longer than the Mac mini. Superglued 2 rubber feet on the wrench at the same location as the thumb indents. Put the Mac on the ground, between my knees and used my body weight to turn the cover. Worked like a charm.

The 3rd screw needed a T5, for me.

All of mine have 3-T6 screws.

I can't, for the life of me, get the left screw out of the cowling. Had to pull both out together. Now having a very hard time getting the cowling back in to replace the fan.

I can’t remove the left screw to separate the fan to the cooler. Impossible to put back the fan and the cooler.

One of my fan screws don't come out, even though I keep trying to unscrew the screw. I tried a lot of things ranging from pulling the fan up to just trying to shake it out, please help me out with this

Only two screws as stated above need to be removed but as people have found out, the one in the cowling can bind into the post below it and it’s the post below that unscrews instead. So you end up with the screw+the post+the fan all together as one. That assembly can be worked out, and then with two pairs of pliers the post and screw can be separated.

The lower right T6 fan screw is a standoff (that also secures the logic board). This can be loosened and kept with the fan, or (since it is friction captured in a grommet on the fan), the fan can be lifted off, being careful not to dislodge the grommet.

IMPORTANT: there’s a spring under the post which could go anywhere when the post comes out with the screw.

Hi… Hi… Good. I have a query, I want to change my internal hard drive from my Mac Mini (mid) 2011, and my query is whether to remove the fan screws and other parts, which from what I was informed is the Torx T6 screwdriver. And my question is: to remove it I need a Torx T6 screwdriver with a hollow point or the Torx T6 with a flat tip will work for me. From what I have read, that the hollow point Torx are called Precision Torx or are identified with an "H" after the number in this case: "T6H". The same query is to remove the cover where the WiFi is, should I use a Torx T8 hollow point or does the flat point work for me? From now on I thank you get me out of this doubt, before doing something wrong. Thank you very much and greetings. Image (Augusto)

After having a look on YouTube at various methods I found it was not necessary to disconnect the fan or the antenna plate. I rotated the antenna plate out of the way and secured it with a piece of masking tape. I also found that I didn't have to move the logic board either. I lifted the HDD connector (gently) with a spludger . The original HDD came out easily once I managed to grip the plastic PCB cover (which isn't needed on the SSD) . Fitting the new SSD was easy using a masking tape 'handle' in the shape of an upside down 'T' . funnily enough the hardest part was getting the little plastic shroud on the left to sit nicely but even that was easy once I had used the masking tape 'handle' I'd used on the SSD. I always think the less you have to mess with the less chance of anything going wrong. Oh, and buy a antistatic wriststrap !

For me it was no prob to remove the fan just pulling carefully upwards.

Mid 2011 Server, I had to remove the fan screw

Mid 2011. The "yellow screw" from step 14 is captive in the fan and has to be removed in step 4.

Also it is much easier getting the fan correctly aligned on the stand of rubbery bit if you have the screw removed.

It’s no need to remove the screw

I ended up removing the complete stand off post.

My whole fan connector just broke when reconnecting

I've just pulled out the connector that's soldered to the logic board because I used a pry tool. Be careful at this point to just pull gently on the four cables that go to the fan.

The CAUTION in step 13, "Make sure to pry up from beneath the wires and not underneath the socket," applies to this step as well, for removal of the fan wires.

I screwed it too... Not reading carefully enough, I accidentally removed the whole socket from the board. This happened with the IR connector too. When re-assembling the parts, the socket wouldn't stick to the board, now I know why. I don't want to buy a new logic board, because I can't afford one, so I'm trying to find someone to solder it. Seems hard to find someone able to repair logic boards these days. Hope I'll be successful, otherwise this is an expensive upgrade to my mac...

Don't remove it with your fingers, use a tool for that. And underneath the wires!

I broke the fan wires from the connector plug. Impossible to repair. I have ordered a new fan. Is there a correct orientation to plugging in the new connector?

Does anyone know how to solve the full RPM fan issue? My computer guy couldn't solve with fan control software

I removed the fan and everything worked fine, but it’s good to know that it’s a “push-down“ connector, took me some time to relize that, all I needed to do was to press down the connector over the pins, see the picture for more details.

SO glad I read these comments first.

I changed the directions to read:

“Use a Spudger to carefully pry the fan cable connector UP out of its socket on the logic board.“

You guys DO know you can edit these, right?

The direction you “ gently pull” to remove the connector is all important. You have to pull upwards, vertically away from the board. If you pull more downwards parallel to the board, you may end up wrecking the connector by pulling the wires out of it as I did. Fortunately the socket was okay so it was just a case of buying a $10 replacement fan (complete with new connector).

DAGNABBIT! Broke it! Now I have a fan blowing on the open case while it’s operating. What can I use as a shield for dust but still allow for airflow?

really wish i would have seen these comments before I ripped out the fan from the logic board.

I missed the word UP and instead pulled the wires straight out, which ended up with me holding the wires but leaving the plug behind in the socket. I just ordered a replacement fan from ebay, since ifixit is out of the one in the correct amperage for this unit.

I then edited the guide to capitalize and bold the word “UP” and hopefully that saves somebody else a bit of hassle.

Any step with a lot of comments is one people have trouble with. It might be useful if ifixit were to make it more obvious we should read the comments, at least for those that have a lot of them. It would save a lot of people a lot of hassle.

Just for emphasis on this point, I did exactly that - I ripped the fan connector right off of a perfectly good logic board. I used a plastic pry tool and was attempting to follow OWC video for replacing the drive. So beware! Trust me, it is not that hard to rip this thing off the board.

DO NOT REMOVE THE FAN.

Put it to one side.

Here’s a video showing how this is done: https://youtu.be/KlR-RWtqzis

Note That the arc of the cowling does not butt to the edge of the chassis. But slides in below it. Once the two screws on the heat sink are aligned with the cowling holes, it's good to go.

used a T7 head to get this one out.

Does this screw have a spring attached to it?

This is one of the few problems I had when reassembling because I didn’t realise at first that the cowling goes just under the lip of the outer case rather than just butting up against it; once done, it’s easy to line up the screw holes.

Thank you Carrick!

The "engineering tolerances" are definitely tight for the AirPort antenna plate. I would recommend trying to replace it as soon as it's removed for the first time, in order to work out the (precise) alignment of it.

Nothing I tried (including the suggestions here) seemed to help me during reassembly. No matter what I tried, I couldn't get the holes for the two 5.0mm T8 screws to line up. Eventually, I had to resort to CAREFULLY and SLIGHTLY re-bending the curved edge of the antenna plate.

REATTACHING grate - al dente's trick helped me.

The tiny perforations on the grate rest ON TOP of the lip of the case, while the remainder of the grate slides UNDER the lip. It is very hard to see - I used a magnifying glass.

To get it into place, create a tiny hook on the end of a paperclip. Moving along the edge of the grate, lift a perforation with the hook to help it slip into place. Keep moving along the edge until entire grate is shifted into place.

I had several 2-terminal connectors that went to what appeared to be temperature sensors on several components including the hard disk and optical drive. I accidentally pulled the wires out of one of these connectors. Lucky for me, they came out clean and I was able to just re-insert them into the connector

On a Mini bought Jan 2014, Red screws were T-9 and orange were 2mm Hex, T-8 didn't work in either one. T-9 didn't work in orange.

As everyone else has noted during re-assembly, seating the antenna plate is tricky. For me, what ended up working was to attach the hard drive screws first. After this, with just a little wiggling of the plate, the 2 5mm screw holes lined up perfectly.

Aligning the drive holes with the ones on the antenna grate was easy – just take the pointy end of the spudger. Also, for getting the circular part of the grate set correctly, I had to bend down the outermost part a tiny little bit and then used curved tweezers to lift the grate once it was near its final position to get it slide in the last millimeter. Frustrating at first, but it worked after a few tries.

The antenna plate seems to give most people problems. Somewhere along the line I found reference to "a wiggle here and a wiggle there" and that seemed to work. Shy away from the brute force - it's the surest way to damage something.

Steen Rancher January 12, 2015

If 5.0 mm T8 holes don't line up with those on the body, you should hook the antenna up a bit.

Despite all the efforts, I couldn't manage to insert both side screws for the antenna plate. I ended up only using a single one (the one nearest to the HD connector), hoping it will hold the weight of the SSD.

Same issue with that antenna plate - take a look at it from the side and you will see the incredibly tight gap which the lip of the case needs to slot into. I assumed it simply butted up against the case, but no.

I used a big paper clip as suggested here, putting in one screw and then lifting through the perforations while applying a little pressure to the plate. Turned out there was one point misaligned and after a few tries it popped back in.

The thickness of your hard drive or SSD plays a part here, I think. With a thicker SSD (Crucial M4) in the upper slot I found the antenna plate very hard to re-install. After replacing this with a Samsung Evo 850 it was much easier, I think because the lower drive has more room to breathe. With the thinner SSD I didn't have to remove the power supply, either – a major plus.

For those having trouble reinstalling the Aerial Plate, it is probably a matter of alignment. The recessed edge of the plate slides all the way up under the lip edge of the case. I used my iFixit bent tweezers spread and inserted through a couple holes to lightly pull up on the grate while pushing on the flat edge. No hard force was required. It just snapped right in. You'll know when it is home because it will be a snug fit to the edge of the case inside the arc of the opening.

I would also add that during the reassembly process, make sure the drive stays firmly seated in the grommets. There's a tendency for it to come out or partially out. I kept nudging on it to make sure it was fully seated. Then the antenna screws line up nicely. Some of the problems I read about getting the screws in I suspect arise form the hard drive not being fully seated.

Al Dente and Chris1000 provided the key for me. I used the logic board tool to help lift the cutout sections into place on the top part. Once I did that I slid in to place so easily I almost pulled it out of place trying to adjust it.

Hilariously, I was trying all the tricks, with the paper clip, and putting the drive screws in first, nothing working for me to get the case screw holes aligned. I ended up saying “one screw might just have to do it”, so I put the first case screw in, then I tried putting the second one in from an angle into the misaligned hole, and screwing it in, and that caused the plate to pop into place!

What finally helped me was to check things one at a time. To check the tongue-and-groove fit, I installed the antenna plate by itself, with the hard drive removed. I used a spudger to pry open the groove on the antenna plate, since I had closed it a bit by forcing things. After the antenna plate was going in by itself, I focussed on the hard drive. At first, I was pre-attaching the hard drive to the antenna plate, but this makes it hard to see if the hard drive is going in as far as it should. Getting the two protruding screws on the hard drive into their holes is tricky (I found turning the Mini upside down to use gravity helped), but for me it was some wires at the side of the hard drive space that were getting under the drive and making it sit up high that was the problem. Once I got the hard drive in, and then the antenna plate, I could get the last two screws which hold the drive to the plate to catch by turning the Mini upside down and tapping it on top to bring the hard drive close to the plate.

So, what they mean by the “paper clip” trick is that you need to lift away the round edge where the wire runs, to be a little further away from the plate. Then it will fit without forcing it.

In order to put back correctly the 2 Torx T8 6,6 mm in the hard drive through the airport grid, I used a pick (to play guitar) to lift up the hard drive in order for the 2 screws to reach the hard drive holes.

I inserted the pick in the little space left between the mother board and the hard drive. Then, by leaning the pick against the motherboard, it lifted up the hard drive against the grid. Then it was super-easy.

Hope it might help…

The flush screws holding the hard drive to the mesh plate are actually T9 torx. The other little screws on the left and right edges of the mesh plate are T8.

No I disagree with all of this … this is plain and simple extremely difficult bordering on impossible and I now have to take the mini to professionals and pay them to see if its salvageable .. so moral of the story I wasted money and time trying to go DYI and I learned the hard way.

In my case the two center screws on the antenna cage do not physically connect to the drive. They're just held in place with rubber grommets and do not screw out. All you need to do is remove the outer two screws and the antenna can be removed

The two outer screws which also holds the bottom plate won’t fit anymore. It seems that the wholes for these screws lost their tight fit, the screws just drops in and falls out again… bummer, now the bottom plate doesn’t stays in place

On reassembly, I could engage either one of the two ears, but not both at the same time. _Lifting_ the antenna plate slightly with a paperclip bent into an “L” and inserted through one of the holes close the the center of the curved edge did the trick for me.

Adding 2nd drive to Late 2012 2.6GHz i7 Mac mini

This is as far as I had to go with disassembly.

Disconnected & eased out original 1TB HD. Removed the two grommets on its side and switched the 1TB HDD with the new 2nd drive cable (not quite the same as the one illustrated here – mine consisted of just the cable and no cradle ). Eased that HD back in and attached it to the previously spare drive socket on the logic board (with drive at the top, right-hand looking down). Screwed 2 grommets into my new 500GB (7mm) SSD, attached old drive cable and eased the SSD in on top of the old drive. Connected that drive to the first logic board socket.

Took a while aligning the antenna plate and the 2 inner screws didn’t seem to line up with the new SSD so in the end I left them out. Everything seems secure, though. Cowling slipped back in place with no problem and that was it.

Currently cloning the old HDD onto my new SSD with Carbon Copy Cloner. So far, so good. Can’t believe how easy it was – just 10 steps rather than 37!

On the Late 2012 model the antenna connector is hidden under the case, so unlike as indicated in step 10 you can not see the connector and definitely not remove it until the Logic Board has been eased out an inch. Note how the cable makes a loop under the case as it is removed. Remember to reconnect the same way with the loop and connected before the logic board is pushed in all the way.

The antenna connector is underneath a black flap. I just lifted the flap slightly with a spudger and used my fingers to disconnect.

...in the latest delivery of the mac mini they had changed something. The antenna plug is hidden under a plastic cover and some tape on it.

You have to push up the cover and remove the tape...not really difficult, it was formed so you can put up easilly.

If your machine came with a 7mm drive and you are replacing with a 7mm drive you do not need to move the logic board. I installed an Intel 335 240GB drive which is a 9.5mm drive and to get that drive in I did need to bump the logic board out to clear the memory slot brackets. I did not need to remote any other wires or connections as the logic board only needs to move maybe an 1/8" to get the drive to clear the memory bracket.

I skipped this step with no problems.

I have a late 2012 Mac mini, but it must be an earlier version than this late 2012 Mac mini in this description, because removing the hard drive is much more complicated than described here. Please see this YouTube video if you have trouble removing your hard drive with these directions. https://www.youtube.com/watch?v=cvmuQIZP... There is a longer process you've got to go through. It can be done, it just takes much longer. (3-4 hours for me)

I think sandyfacebook is speaking about the mini server with the second drive this guide is about replacing the primary drive.

BTW, I agree with radioman: it MUCH safer if you do not need to remove the logic board to replace the HD. Just stop after step 12 and pull the drive out. The trouble starts when you try to put it back in because gravity is working against you: the drive has to hang in its slots about 1 cm above the top casing, which is on your table. The trick is to flip the mini up onto its front edge and after a couple of tries the buttons on the HD will engage their sockets.

Am unable to reattach the cable to its socket on the wireless board of my late 2012 (after installing SSD as second drive). Looks roughly the same as pictures here, but won’t attach. Anyone had problems attaching and figured it out?

On my late 2012 Mac mini, I could not slide out the lower drive without removing the logic board; the memory cards were in the way. Radioman’s suggestion may work for some disks, but not for mine.

Thanks sandyfacebook, I also had a 2012 Mac Mini (not the Server version) where the Primary drive was installed in the top (that is to say, lower when the Mini is upside down to be worked on) drive slot. This meant a complete disassembly was required, removing the logic board completely, along with the PSU and lastly the lower drive caddy. Unlike the drive shown in the pictures, the one underneath is secured into the caddy with screws and cannot be just lifted out.

You can gently use the tip of a screwdriver to align the antenna plate screw holes as long as your hard drive pegs are aligned. *DO NOT FORCE* as your hard drive may just not be in the right place.

On my Late 2012 mini, the antenna plate connector is covered by part of the case. But, as FinnCrisp888 said, there is actually no need to remove the antenna plate at all; just carefully fold it back to expose the bottom drive.

Has anyone figured out how to reconnect the antenna wire back to the logic board?

The server version of the MacMini 2011 has three extra two wire cables for temperature sensors: two on the drive directly under the antenna plate, one on the other drive.

The small connectors have to lifted up from the logic board just like the fan connector and the IR sensor connector.

Take care when transferring the sensors to a new drive because two of those three extremely tiny PC board need to be removed of the old drive and are glued in place.

The "pop off" seems only to happen during reassembly if you press on the harddisk body. The harddisk at this time can be pressed in the direction of the underlying drive (in my case a SSD Drive) . Once the grid with the antenna has been attached (two red screws in step 8) this cannot happen any more.

I also just snapped this off by levering at the wrong point. So this is just for the IR sensor and the flashing light? If so, I'll just ignore it and happily carry on with life without these two features that I never used or noticed! I've been searching for someone who can do the delicate welding to reconnect the 5 pins but if what you say is true I'll stop searching.

Recommend emphasizing even more in the instructions, the potential for disaster!

TerribleHacker: "pull it out parallel to the logic board" – no, or at least not on mine. The pins are vertical and the socket has two vertical tongues that fit into grooves on the plug. Vertical is the way to go. In cases like this I use tweezers to pull gently on the wires, and if possible the plug – but the latter is very difficult in this case.

Yep. Like others here I no longer have IR. Be VERY careful removing this!

TAKE YOUR TIME!!! I used the spudger and pushed up from the back on the plastic, NOT the wires. And I had no issues. Pulling on the wires scared me way to much. Pull up vertically.

Before attempting to remove the connector, use 5 minute epoxy to glue the wires together. Do this in several small batches and apply with a toothpick, right up to the plastic connector, but not glued to the connector (to risky and not necessary). Be especially careful not to glue to the motherboard. You basically want all 5 wires glued together as if they were a ribbon cable. After the epoxy is cured, pry up from underneath the wires to remove from the motherboard.

I could remove the HDD and then was able to use the folded spudger from the hdd side of the motherboard to _easily_ pull the connector up from its corners (not via the wires).

I lost my IR sensor and HDD led light as well. Everything was moving along smoothly and I got cocky with the spudger and lifted the connection out of the board. I reassembled with the upgrades and it ran just fine. Like others, I had never used the remote and couldn’t see the HDD light where the mini sat on my desk anyway.

yes, there is a way to FIX it, solder it back ! :) that’s what I did on mine

The best way is to first remove the logic board already 0.5 cm out, like discribed in the next steps. Look closely at the wires, they tell you how far you can go! Then take a cotton swab, cut off the cotton ends ending witha plastic stick, bend the end to get it easily under the wires and pull it carefully upwards. The connector then comes off in one piece.

The best way is to first remove the logic board already 0.5 cm out, like discribed in the next steps. Look closely at the wires, they tell you how far you can go! Then take a cotton swab, cut off the cotton ends ending witha plastic stick, bend the end to get it easily under the wires. Take both ends and pull it carefully when it is as close as possible to the connector. The connector then comes off in one piece.

Must really concur with Bas Meijer’s suggestion. Move the logic board slightly first then it is a breeze to get under the wires and lift up.

As the warning says “pry up beneath the wires, not beneath the socket”. The connector lifts out, but is surrounded on 3 sides by walls of the socket. Don’t lift the socket off, lift the connector out. Easier after step 14-15 and you move the main board out just slightly.

Does anyone know what is the name of the connector cable side ) I want to buy a new one as mine is damaged and repair it.

I am also wondering if I can purchase the side that was on the mother board?

Unfortunately I bent two of the pins in the process. Moving them back into position broke them, although I was very careful. I felt so stupid. Who the heck at apple thought this is a good design to connect things?? I thought the mini is already lost. Happy to read this cable is not super important, so I will carry on.

this yellow screw come from fan , on the image in front missing exactly this one screw (yellow circle)

any idea in how to remove a stuck the "green” screw ?

The yellow screw (fan stand off) on my late 2012, was removed with the fan.

Look at all of the images. Initially, I took the text literally. I pulled the tool straight back without letting it pivot, and without success. I suggest the following additions: "The tool acts as a lever. Carefully pull the top of the tool down and toward the I/O board. The logic board and I/O board assembly should slightly slide out of the outer case."

If you don't have the removal tool you can just plug an ethernet cable into the I/O port and pull on it to help ease it out...if it's a bit stiff push on the fan duct at the same time...be gentle and it'll release...

I found that there is one step missing for removing the logic board. Once you have the removal tool in and pulling back check to see if you can push in on the taps that are on the outside of the logic board. On the right side if I had known this I would have tried pushing in on the tap and it might have released a little easier. There is not a good photo of the taps but in photo 17 between the pointer and index finger the tap is located on both right and left hands.

Even better, you can just use one of your screwdrivers if you do it carefully, just push out each side a little bit and rock out the logic board. No special tool needed. Just be careful not to damage your logic board and/or apply too much force.

If was able to fashion a removal tool out of part of a metal binding clip. I just removed one of the handles and bend it into the proper shape using a vise. FYI, the holes are about 4.5mm apart.

I’ve used an Allen key of the right diameter.

it worked very fine!

I just pushed on one of the RAM slots and it slid out easily. No metal rods required!

When reconnect it on the board, make it when the board is in the middle of the mac, or you will be not abble to do it!

I'm not a fan of pulling on cables so I used the flat end of the spudger and pried between logic board and light thicker end of the DC plug. This took some time but worked really well.

I found that slightly lifting the board allowed me to get the connector in a better position to rest on its female counterpart. Then with a smudger just push it into place.

When getting it back on during reassembly, your spudger is your best friend.

Do this when the logic board assembly is not completely inserted back in again.

If you removed the hard drive during disassembly, when reassembling you'll want to put it back before sliding the board back into place.

Does anyone know if the airport/bt board from a mac mini late 2012 can be retrofitted to the 2011 mini? this would add the airdrop functionality to the older device in theory and I have seen a similar procedure performed on MacBook pro's

During reassembly, the SD Card reader end of the I/O Bezel will not go back in flat like the AC power connector end, thus the SD Card reader end protrudes about 0.5mm from the edge of the back of the MacMini, I tried took it out and put it back in many times but could not manage to push it all the way in. The truth is it is hard to notice and everything else works fine but it is annoying to see that tiny bit protrusion. Anyone else had this problem? or it was like this already before I took it out? i can't remember what was it like now.....

During this process, I took advantage of having the logic board out, checked the BR2032 battery, which tested nearly dead, and I replaced it with an ECR2032 battery. If you choose to do this, be careful with the moving and replacing of this button battery. There is a wee-little directional arrow on the ( - ) side of the battery holder, which means move the battery without prying towards the positive ( + ) side. One end of the battery then pops up to grab. I also tested the new replacement battery before putting it in. I used an AMPROBE BAT-200 Battery Tester.

So near and yet so far. Got as far as this stage only to fail.

If you look closely at the photo for this stage, just up and to the left of where you unplug the power cable, you will see a white wire going into a grey sleeve attached to a grey plastic plug of some description. That’s not what I have. What I have is five wires, two of which (one black, one brown) have tiny copper clips which suggests that they were attached to the logic board. The other three wires (two black, one grey) look like they were torn off and damaged during the removal. I’d post a photo but there doesn’t appear to be the facility for it.

C’est la vie.

Would it be possible to insert the lower disk at this step without removing all the remaining parts ?

I achieved to insert the lower disk at this step without removing all the remaining parts !!! You just have to screw the HD on the other side (motherboard side).

I too, took advantage of replacing the 3V #2032 PRAM lithium battery. Doesn’t make sense not to, since it’s completely torn down.

I found that cloning the new SSD drive before installation sidesteps 'hybrid' drive issues.

I didn't disconnect the antenna cable since it's very tricky to reconnect that tiny connector.

The original drive in my unit is positioned at the bottom and I couldn't get that out without dissembling everything so I just left it in place and disconnected the cable.

I moved the logic board back about 2" to give me some wiggle room inserting the new drive.

I couldn't get the new drive to fit into place with the rubber washers inserted on the posts so I just used the posts instead which gave me some more room to push the new drive back far enough to fit into the positioning holes.

Even then the cable for the new drive took a lot of effort to connect to the board since I think the new drive still didn't fit perfectly above the older drive.

I used scotch tape to help position the new SSD.

Overall a huge speed improvement from the old spinner.

For me this was a more than moderately difficult project.