all great info guys.
after the 80 grit i've been told to go over everything with 120 and then prime, but priming the 80 grit next will save that step? (and quite a bit of work)
If you used regular sanding paper it might leave a deep scratch. If you used a DA don't worry about it. Steel
wears out paper pretty fast. Just degrease the metal good to remove any residue and skin oil which can come back
like a thumb print. I know this from experience.