I replaced these turn signal lenses shortly after I bought the car. The lens covers quickly went milky in the sun and the rubber seals perished in no time.
The areas of the lenses are covered by the fake plastic chrome cover still look immaculate.
The Sprayway glass cleaner did a great job of cleaning them up, but the exposed areas were still rough and sun baked.
I questioned whether or not to just put the old assemblies back in. The lenses are clear and still fully amber, but are crazed and cracked all over, which is why I replaced them in the first place.
I have used this Kit Scratch Out in the past to clean up foggy plastic headlight covers.
It did polish the roughness away, they are now slick and shiny, but still cloudy.
Did I mention the rubber seals are perished? Either way, the lenses look 40% better than they did a few minutes ago.