I am restoring a 67 Chevy II that I have had since I was in high school (I am 32 now). When I was 17 and dumb I cleaned the chrome trim around all the the glass with chrome wheel cleaner. Dumb! Any way the stuff ran on the glass and ever since it has had a rainbow looking mark where it ran down and evidently etched the glass? I was thinking maybe there is a film on glass it damaged? How should I attempt to repair this???