To clean up rusty rotors I set them on a big 'lazy susan' bearing and let the sander turn the rotor so it's done evenly all around. Of course my rotors have more rust than that one!
Back in the day I would use gasoline and fine grit emery cloth by hand to resurface a flywheel. It always worked well for me. I'm talking mid 60's here. I'm sure that things have changed since then.
Have to appreciate a guy that will cut a window in the floor to get the world's toughest bolt out. No problem just welderup! The car should stop, steer, and ride well, that covers most of the bases! Horribly hot here the past couple of days, I had a dose of heatstroke yesterday and was on the ground for a bit. Luckily the old Chevy blows ice cubes and someone handed me a bottle of electrolytes. I chugged it and sat in the truck for a half hour.