Does anyone have any experience, positive or negative, polishing scratches out of auto glass? My GTX has scratches that don't catch the fingernail, but you can feel some of them. I bought some cerium oxide powder, but before I bother finding a felt pad, etc., wonder if I'd be better off just springing for a replacement door glass. My plan was to try to polish the glass on the car, but suspect that could be quite messy. Input appreciated.