Restoring bare aluminum finish on wheels?

I'm going to re-paint my turbine wheels, but before I do that I want to clean up the lip area so I can leave it unfinished. There's something that looks like either mineral deposits or peeling clearcoar on some areas, and I can't figure out how to remove it. Scrubbing with a scotchbrite pad and degreaser didn't even begin to take it off, and rubbing compound & metal polish didn't help either.

Originally I had wanted to polish the lips, but I think that would probably be a ton of effort... although I do have a dremel tool that might speed things up. If nothing else I'd settle for just cleaning them up nicely and restoring the stock aluminum finish though. Any advice?

Are the turbine rims clearcoated from the factory? If so how should I go about removing it?

The inner areas of the wheel do not have the same white substance that the lips on all four wheels do. That's why I thought maybe it's some kind of oxidation... The aluminum wheels on my old Acura (which were a similar machined finish) had the same white stuff on them.

I wasn't planning on totally stripping the center areas off the wheels as the finish is still level... just scuffing them well and using wheel paint.

Yeah I've used that aircraft coating remover before and it definately takes paint right off. Will it damage or discolor my tires though? I just had brand new BFG's installed so I don't want to mess them up.