You totally don’t need the one-use-only “logic board removal tool”, that’s silly. If you push against the heatsink with both thumbs (being careful not to make the board flex) and wiggle it out it’ll eventually give and slide out.

This guide can also be used in cases where your Mac Mini has been pre-installed with only the second drive bay in a bracket, from manufacture. Apple made it deliberately difficult by mounting the stock HDD in this model in the second drive bay so you have to disassemble it to get in and replace it with a much faster SSD. You essentially follow the guide until step 24, install the SSD in the bracket with the four T10 screws, then follow the guide back in reverse order assuming you only want the one drive and aren’t installing a second with the kit. This is what I did, so this guide prevailed where YouTube failed as all the ones I saw had the drive in an easy to reach place.

Most times when I take something apart, when I put it back together again I’ve missed something, or something doesn’t work or what have you. This time with this guide, other than lightly trapping the camera wire under the logic board (luckily before I’d plugged that many things back in I noticed; good order to the guide) everything went back together smoothly so far the iMac feels a lot snappier. The SSD hasn’t arrived for it yet but when it does, I think it’ll be good for several more years of quality computing.