Started with a couple side scoops for a Yamaha VMax motorcycle which previously had been painted a hideous black semi-gloss, and which were scarred considerably. Rustoleum aircraft paint remover, several applications, finally got them mostly-clean. I used a fine wire brush in a 4-1/2" side grinder to remove the stubborn stuff, but decided I didn't like the way the wire brush was working the aluminum of the scoops.
I tried some #400 wet-or-dry sandpaper by hand. That seemed to help with the wire brush marks. Then I broke-out a d-a and used #800, which was much quicker than the hand sanding. It did a good job and things started to look more-even.
I have a vintage B & D two-head benchtop buffer w/muslin wheels, and started to use the white stick, and spent some time on the scoops. That gave some decent results, but I think I'm about ready to price-out having them finished professionally. It's not going to be show-quality, I just want them to be uniform and smooth. If the prices I get-back are above my budget, I'll probably just paint them. More polishing might make the paint not have enough 'tooth' to stick, I'm thinking.
I'm not a pro metalworker or mechanic, just a hobbyist staying busy in the garage with a project.