I just finished doing my second battery replacement on one of these. If you're replacing a battery that came from iFixit you can skip straight to step 34 and use cards/spudgers/guitar picks to remove the batteries. The adhesive on the iFixit batteries isn't nearly as tenacious as the original Apple adhesive (though it's plenty to keep the battery stable) and it was easy to pop the battery segments out with a spudger and peel up most of the excess adhesive strips. What little was left came off easily by putting small amounts of the solvent on paper towel and rubbing - no need to pour any amount of solvent into the case.

I just did a second battery replacement on an identical model using fishing line (30 lb test) and no solvent instead of the string and solvent. It went about the same - the fishing line cut through the adhesive tape maybe a little easier, but also requires a little more care because you can slice your fingers with it. I wrapped it around two short screwdriver stems. It helps to wind it up so you have only a short length to work with and use your thumbs to push the case while pulling the line. It went through the tape easily, but left it stuck a little harder so it took longer to remove the last bits. Isopropyl alcohol (91%) works almost as well as the acetone/isopropyl mix in the ifixit kit. Using the spudger to peel up the tape helps - a few pieces came up nearly intact with no residue on the case. Having done two now, I definitely think string/fishing line to separate the batteries is the way to go.

On a different model macbook I got a bloated battery from leaving it connected to the charger all the time and never discharging. I wasn’t traveling, so it never really got unplugged and discharged. The bloating isn’t necessarily from low cycle count as from extended periods staying on charge - it was replaced under warranty and they recommended taking it off charge and letting it run down at least once a month. The replacement has continued to function for many years.

I just replaced a battery using the string technique and it went great . Battery had over 1000 cycles, no bloating. I used the “thick” string like in the video - smooth multi-strand string that I use with a string level outdoors. I moistened the string with the iFixit solvent (a mix of IPA and acetone) and pulled it through with a gentle side to side motion. I had no problems with batteries sticking back down, though I initially used the cards to prevent it. Most of the residual tape pulled up cleanly, and I dissolved the residual adhesive with small amounts of solvent. The total amount of solvent I used was very small - the bottle is still nearly full (I didn’t check the level at the start, but it’s about 7/8 of the main bottle).

On one battery (central pair, left one) a piece of plastic unfolded to make it hard to get under, and the string dried out while I was doing that. Dry string is very hard to pull through, but just moistened with the solvent made it easy again.

Just finished this and it fixed my GPS. Wifi and bluetooth had been fine, but GPS died suddenly, making things like google maps useless for driving. I verified it was a GPS problem by downloading a GPS app that shows the number of satellites it’s locked on. The procedure is very straightforward - I printed the whole thing out and put pieces of tape at each step near the pictures of the screws & small parts to keep track properly. If your iphone hasn’t been bent or anything it all goes back together very smoothly. Steady hands and the screwdriver/tweezers/spudger kit helped. I also used a ground strap (from another ifixit kit) during the procedure and nitrile gloves when handling connectors.

And to add another comment on dealing with the connectors - I found getting the tiny coaxes aligned and mated about the hardest part of this, since I wanted to be careful with the logic board and it takes some force to mate the connectors. It turned out that supporting the free part of the board under each connector with the flat of one spudger while pressing on the connector with a second spudger worked well. Starting with the furthest out connector to the right in the picture also helped with keeping it aligned while I did each of the next connectors.

My replacement flex cable came with a little bit of blue film over what looks like the antenna patch with no notes on whether to remove it or not. From all the pictures (and the old antenna that doesn’t have it) it looks like it should be removed, but it would be useful to have a note about it either with the part or these instructions.

It’s a pretty straightforward job - the instructions are very accurate and well detailed. The things to watch out for are that steps 7 and 6 should probably be swapped, and be careful to slide the display data cable parallel to the logic board rather than “pull”. The coax connectors for the wifi also pull off easily - one display I received was missing one, so I transferred a connector from the old to the new one, carefully spreading the crimp with a safety pin then recrimping. I got a little too much practice because the first replacement I got (not from ifixit - they were out of stock) had a bad backlight, so I had to swap my old one back in (and try the new one again…, then the original) so I did it about 5 times total. I have some stiffer blue spudgers that are more scraper-like from the ifixit kit that work better than the black pointy one for the wide connectors.