I have a set of rims that are in good shape, but have some kind of film on them. I powerwashed most of it off but cant get it all.
It's looks like some kind of clear coat that got to hot and turned yello. Or maby the previous owner had them tinted gold. Not sure wich.

Anyway you can see a pic here (top one)

 

I am currently polishing a set of those. I used Tal-stripII aircraft stripper in an aerosol can. Cost 6$. If you use that can, buy two. I needed two but the shop only had one.

Spray it on, or paint other stripper on with a brush, let it sit for 30mins and i powerwashed off with a heavy duty power washer and the finest spray posible.

Took most if not all of it off. The rest came off with sanding because I am polishing them. Dont get it on tires!!

 

It took me 3 cans to completely strip all 4 wheels.

Aircraft stripper is the way to go, spray on, let it sit. Peel off paint.

Wear heavy duty gloves, cause the stuff burns like hell if you get it on your skin and dont get it right off.

 

I didnt want to use anything that potent. The finish under the film is still in good shape. 70% came off with just powerwashing. Any other ideas?

 

Under that film is just bare metal. Only the black parts on those wheels in the pic are painted. You could use a stripper and be sure to apply it with a brush and avoid the painted parts.

Under the yellowing clear on the lip and the outer face of the spokes is only bare metal, no paint! Correct me if I am wrong. Thats how my 92 z28 wheels are.

It looks like the person that "refinished" those wheels before you sprayed on a clear after doing his "refinishing".

 

if you dont want to use stripper, just go at it with a sander and polish. will take longer, but wont threaten the black paint