By definition, "unscrew" is in a counter-clockwise motion. And, people who are taking apart a device like this will be able to tell when they try to turn the screw which way is correct.

In the second picture, there is a hard disk. In the first and third pictures, there is no hard disk. You might want to update these instructions to include hard disk drive removal.

this would have been a great place to include a picture of the other side of the motherboard. to see the PCIe slot, for instance.

Sooooo, there is a PCIe socket for an SSD, or not? There is no guide for changing one, but it seems the port is there.

This repairability score seems particularly harsh to me. Pentalobe screws - so? You get a tool and you can open it easily. Battery replacement - yes, difficult, but possible, especially with the guides provided here. SSD - easily available so that comment is overly harsh. I'd give it a 3 or 4. To me, "repairability" is the ability to be repaired, not so much a commentary on how difficult it is. Several components can be replaced, so that's good.

no! don't do that. if for any reason in the future you need to open it up again, you will only destroy your screen. you can get strips really cheap on Amazon.

So, the bit about the adhesive strips really needs to be clarified. Nowhere in the instructions is there talk about multiple layers of adhesive, one that should be removed and one that should remain. And looking at the pictures further on, clearly the wider sections where the adhesive go are completely clean of any black strips. However, on the screen side, I’ve noted that indeed there are two layers, at least on the top. And removing both layers leads to the adhesive *not* really taking hold and the screens falling out. Really wish this had been clearer. I’ve helped dozens of people upgrade their iMac but after the first time that I had to replace a screen due to it falling and breaking, I’ve been using clear strong adhesive tape externally on the corners to ensure that the screen stays in place. Ugly, but better than the risk.

I got a 4 TB Seagate Barracuda HDD as a replacement for a client. (Going for capacity over speed.) Does anyone know if it will fit? It’s definitely fatter than the other HDD/SSDs I’ve installed before.

A fusion drive combines two physical disks via software to act as one. It it something that has to be done manually and expressly. When you first got the computer, your fusion drive combined disks A (SSD) and B (HDD). If you replaced B, then you probably have an unused 32 GB blade SSD along with your new SSD. It possible to create another Fusion drive, but you’d have to start from zero, because creating a fusion drive erases the individual disks completely.

also, not 100%, but I tried for several hours the other day and I’ve come to the conclusion that my version of Big Sur (11.1) doesn’t support Fusion Drives. Correct me if I’m wrong. Or maybe it’s because I’m running Big Sur on an unsupported iMac.

The brand doesn’t matter per se, but it’s helpful to have a disk with the same temperature sensor connector. In some cases, it’s stuck to the disk. In other cases, it’s a long, thin connector with 4 pins. Or, it’s a thick, square-ish connector with two pins. I usually take the old disk to the store and ask “do you have a disk that has a temperature sensor that looks like this?” And….if you can’t find such a disk or you want to stick an SSD in there (they’re getting cheaper by the day!), then make sure you get Macs Fan Control software to help you manage the fans that will possibly run at full blast.

Don’t we need to remove the screws before the next step?