At ten years old, our cars’ plastic headlights were badly crazed. as I tweeted:
A PoliCraft alloy, brass and copper polishing kit from @Halfords_uk worked a treat on tired plastic headlights pic.twitter.com/PEWOeUvvPQ
— Steve Baker MP (@SteveBakerMP) February 1, 2015
Available here. I strongly suggest you keep the polishing head moving: if you let it dwell in one place, expect damage.