To help me line up the IO ports, I filled all the USB ports on the back with thumb drives before I screwed the Logic board back down. Worked like a charm!
The cable in the yellow box pulls out parallel to board. The connector looks as if it might be different, but grasp the black tabs and pull parallel to the board
The middle two cells sit on a black back plate. This protects the trackpad, so you’ll be fine using the cutting wire. The only place to watch out for is right at the top, near the battery connector. If you look just to the right of the battery connector, you’ll see another connector which is for the trackpad. Follow that wire and just make sure you’re careful with the wire around it.
You’ll also find that the adhesive doesn’t start right at the top of the battery. Rather, it starts about 1cm from the top. So, you shouldn’t have any trouble avoiding the trackpad wire.
First off, I recommend having a second set of hands to help hold the MacBook pro in place. It’s probably doable by yourself, but have someone else hold the laptop in place while you cut the adhesive.
Second, we tried using a single strand of cat6 wire. (one of the 4 twisted wires inside a cat6 cable). This was fruitless, because the wire didn’t have enough tensile strength, nor could it sheer anything with a rounded plastic sheath on the outside. We had success with grabber nylon twine, which we use for pulling wires through the wall. Make sure whatever you use has tensile strength and is able to actually cut.
There is foam on the top of this connector. Do not pry up from under that. Instead, put your spudger underneath the red and black wires themselves and pry up. Very little resistance.
I also found this extremely difficult to remove. Tiny cable with a death grip. I tried using two spudgers, my fingernails, and walking it out. In the end, I used two spudgers and pried it up, using leverage from the clip to the right.
Also, i recommend setting the iMac upright for this. I rested the screen on my chest while I dual wielded my spudgers.