If your rims are non clear coated I would go with the sandpaper. If they have a clear coat, I'm stumped, never had clear coated rims, only chrome and aluminum. Currently, I have polished aluminum wheels (non-clear). They were pitted and had all sorts of little atrocities bound to them. No polishes would budge the stuff, so I used some 2000 grit and wetsanded them, then followed up with Never dull, mothers aluminum polish, and finally a coat of Boyd's liquid wax. After about 3 1/2 hours, they looked like new again! Worked for me.