Thanks for all the positive comments. I'm hoping to paint all the bodywork not this weekend but next. Last big task is wiring everything, and I'm already getting started on that.
Polishing the fins was not too tough, it just took patience. I have lots of finned pieces, so I tried almost every method (taping sections off, polishing the paint off after the fact, etc..). The best technique I came up with goes as follows:
I used a sanding disc on my angle grinder to smooth everything out, then a went over everything with a couple different grits of sandpaper, getting progressively finer. Think I stopped at maybe 800 or 1000. Then I painted everything. After the paint had cured somewhat, I cut it off the polished surfaces with a razor blade, being careful not to snag or pull the paint. I basically cut up the paint job while it was still somewhat tacky. When it was totally dry I hit it lightly with the finest grit sandpaper one more time.
After that, most of the parts got baked in my oven (per the directions on the paint) and I spent the next two days eating at the mexican food place down the street with my kitchen windows open.