something to keep in mind when fixing plastic headlight lenses is that they were manufactured with a clear UV protective coating. you can polish and sand all you like and get them to look great but the results may not last. Here's what I did to mine 3 years ago.... sand the lens down with 600# you can go to 100-1500# for even better results, but 600 is fine enough. then hit em with some urethane clearcoat. not rattle can stuff, the real thing, take them to your local bodyshop and have them clear them next time it's "in the gun" if you don't have the means at home. Mine look like the day I did them and I haven't touched them in 3 years, never stored indoors. this even works on yellowed lenses if you start coarser and sand through the yellowed plastic.