PlastX works miracles on cruddy, yellowed plastic headlight assemblies.
I found out by accident a while ago just a little bit on a lint free cloth takes little smudges and baked on bug guts off chrome in no time, and it's safe to use with an orbital buffer for big blemished areas of chrome.
Today, in my effort to black out most of the chrome on my truck, I noticed the vent visors and bug shield had the white manufacturer emblems on them. Unacceptable.
Since PlastX doesn't scratch headlight plastic or chrome, said what the heck.
Little bit on a clean rag, one fingers worth of pressure, they came right off without a trace and without a scratch. It made the area where they were so shiny I had to do the rest of the units to match!