hi SmithLakeChevy, i have had success restoring damaged headlights and other colored and clear lenses as follows (see the original radio dial in my radio restoration post) under running water, wet sand with 600 until all damaged plastic is removed, clear plastic should make a milky white residue in the water, not yellow. again with running water, wet sand with 1000-2000 to smooth the plastic in prep for compounding use Meguiar's ultimate compound to work the plastic until it's clear, use a shop paper towel or kitchen towel, don't add water for this step
optional - finish with Meguiar's ultimate polish to get it better than original surface
if the plastic part will be in the sun it should get a UV blocking hard clear coat i highly recommend U-Pol for a long lasting coating, it is used on modern automotive headlights. if you are applying the U-Pol it is okay to skip the final polishing as the U-Pol will blend the surface anyway
the U-Pol spray can is not like regular spray paint, you will want to wear protective gear and be able to escape the fumes. It is nasty. also i suggest you test it on an inconspicuous place for material compatibility. use a metal instrument to put a dot onto the plastic edge, wait 48 hrs and check that it hardened and bonded well. some plastics might react and go goo-ey and never harden due to negative reactions with the solvents and the cross-linking in the plastic.
hope this helps and best of luck post photos of your progress -stan
