First of all, there are no stupid questions (unless you didn't search and google first
2)The shift knob is supposed to just fit in snuggly -- to click in when you push it in. Maybe one or several of the plastic teeth inside the shift knob is either broken off or is worn. Sounds like a chance to get a new shift knob
3)Although you can use regular, um, "American" fuses in the fuse box, the OEM fuses, or European-style fuses, have teh actual fuse wire exposed at the top. You're fine.
4) Get the shifter bushings from Pelican Parts - Porsche Parts & BMW Parts - Automotive Parts and Accessories - Porsche & BMW
. They have a kit that should run you about $85 or $95 and has everythign you need. This saves you teh pain of scavenging around with a list of part numbers in your hand. They also have the best writeup on the web for this procedure.
5)Your garmin pop-up proect is quite ambitious. I imagine places like newark.com, mouser.com, digikey.com, or maybe ven Radio Shack or Fry's should carry electric motors.
6)Most E36s didn't come with an adjustable steering wheel column. If there is a whole there, it may be just that the plastic cover for where the adjusting lever would come out is missing. Except for in very rare cases, E36 steering columns are fixed.
7)Yes, just rip it out.