I tried Acetone on our '96 Jeep GC. The lights look better than new. I finished them off with a fine polish.
On the MH, it didn't make a bit of difference. I will try the toothpaste and PlastX first but I think new ones are in the future.
I think it depends on what the lenses are made out of. I know that as a solvent, acetone will disolve "most" plastics and severely soften the rest. When I did the Jeep, I took my time and let the assembly dry between the two applications and I was very carefull to rotate the cloth and minimize how much I overlapped the passes plus I did NOT rub. I went in ONE direction only. It turned the rags a very dark yellow and the lights look white now.
BTW, does anyone know what type of vehicle the mfr. got my headlights from?
It is a '98 Gulfstream Sun Voyager Bus. Oh, sorry for posting this in the WB forum but it was related to the headlight thing.