There are "basically" two "safe" methods for removing anodizing.
1. Acid Dip - This has to be done by someone who knows what they're doing. You watch each wheel once the bubbles change color, the anodizing is off. If I recall, the bubbles turn "yellow" and that means the acid is now etching the bare aluminum. Yank them and wash them.
2. De-Anodize - This is the best method. Take them to your local anodizing shop and ask them if they can deanodize them for you. It takes a few minutes. The shop that I used to anodize my wheels did it for free (they knew they were getting my anodizing business).
Yeah, yeah, yeah... there's people that have used oven cleaners and brut force to sand the anodized layer of but, little secret,
those guys are all crazy, whacko, nuts, gonners. (you know who you are, Joe) Seriously now... I'm as much of a do-it-yourselfer (more so) than the other guy but some things it just pays to have someone else do. If you asked those people if they'd do it again I'd have a $20 that says the answer would be "no way". Drop by a plater shop with your 4 wheels in the trunk. Pull one out and ask them how much to dip for a few seconds in their acid tank. They'll probably charge you $10.00. Then you can polish them to your hearts content.
-or-
As mentioned above, save that $10.00 and apply it to your Al Reed bill. After refinishing over 20 some wheels, that's what I'd do.
No painting before anodizing. Anodizing actually etches the surface to create a protective barrier. Paint won't stand up to that and actually get's in the way of that.
If you are planning on having your wheels reanodized then make sure you polish them or have your polisher polish them to a mirror shine. The anodizing will dull and you will then end up with a factory finish.