LIP POLISHING 101:
It's much easier to do this with tires off, but I did two of them tires on (the fronts) and it came out just as good, only took a little longer. Use an air angle die grinder with medium grit 2" scuff pad to remove paint and casting marks in the aluminum. Go at the small outer most lip first, then get the flat area that's about 1/2" wide last. Otherwise, you'll be bumping the flat area and you'll have to re-do it. Repeat with a fine grit scuff pad.
Now, to get that nice machined look, take a green scotch scuff pad and start going around the lip a couple inches at a time to blend out all the lines left from the angle grinder. After about 20 minutes they'll all go away. I don't think you can take too long doing this step.
Scuff the centers with 500 grit wet and follow with the green pad again. Use some pinstriping tape to tape off the polished lip before painting so there's a nice, crisp edge. I suggest stripping that and clearing the whole rim, but if you would happen to knick it, you're stuck trying to repair clear too.
Overall, I spent 10 hours polishing and prepping for paint, and then another 4 hours masking, spraying, and cleaning up.
Here's the only close-up I have, it was after I cleared them: