It was quite clear to me, even though I had never taken a camera apart before.
A few small things that might help others:
- The missing screw in step 25 is underneath the little black tape at the top-right (right under the WiFi antenna)
- you don’t have to take the grip all the way off, you don’t need the 4 screws at the middle, so you only need to pull away the edges at the sd card side and at the top next to the dial.
Also, when I took it apart a second time (I wanted to remove the shims for the sensor), my camera didn’t want to boot anymore and just rebooted again and again by itself. This appears to be a software bug and you might have to disassemble again until step 23. There is a small battery on the other side of the copper plate which remembers the date and time settings, but that needs to be disconnected from the motherboard to fix the issue.