The power switch broke and I had to replace it. It's half the size of a grain of rice and the smallest thing I ever tried to solder on. In the end I succeeded, but just out of luck and sheer stubbornness. Can't recommend that to sane (non-pro) people.
This step is not necessary. Drive can be released without removing the screws.
Yes, that belongs to the yellow screw and is (badly) glued to the motherboard. You'll need very thin pliers to place and fix the nut while reassembling.
I've changed some iPod screens as well and that has been the least pleasant experience so far. Glue and the main connector that has to be unwrapped and connected from the rear where you have no feel or control where it belongs.
iPhone repair is complex, but doable and has very few "traps".
The smallest screw below the Digitizer connector is held by a tiny nut which is fixed below the EMI shield. Beware because this thing can get loose easily.
That was no fun! The iPhone 3G was a piece of cake, compared with this iPod. Especially when the front glass is cracked, it takes ages to get rid of all that glue. I hope I'll never have to do that again. Should be set to "difficult" at least.
After the replacement, the screen was pure white! Luckily, a total reset could fix that. I really was afraid I broke one of the flex cables.