cleaner for yellowing light covers?
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To make them look clear again, I would start with 240 grit sand paper, then 600 then 1000 and finally 2000 grit wet/dry sandpaper, always using water.
After I was done sanding I polished the plastic with Mother's aluminum polish and a dremmel tool. The plastic always came out super shinny and clear. Depending on how deep the yellowing on the plastic goes, you might have to be a little agressive in the sanding to get rid of the deteriorated plastic.
After you have the plastic looking clear again, I would paint them with automotive clear coat paint (2 part) which blocks most of the UV rays.




