When I did my ms pacman, I started with 60 grit discs to get off the old side art, and then I think something a bit higher grit to smooth it out a little afterwards if necessary.
For cleaning/polishing buttons and joysticks, I'll do 220 or 320 grit if there's some deeper stuff, then 2000 grit to smooth everything out, and then rubbing compound (unless I think it will stain the plastic) and wax. I've used this to clean up my DK buttons, atari logo joysticks, and the monroe joysticks on my rampage and have been very happy with the results.
For control panel bolts, I lock them in the drill and hit them with some sandpaper and/or steel wool to get off paint and rust. If they need to be repainted, prime and paint with black enamel paint. If bare, polish them up with some brasso. If the rust goes beyond the head and steel wool isn't getting it off, I'll just order new bolts.
And one of the biggest things for me was replacing my cordless drill with a corded drill. No more farting around with dead batteries, plug it in and i'm good to go. I'm never that far from an outlet anyways, so cordless just wasn't worth the hassle.