I bought a couple of Challenger tail light assemblies for my 72 at the swap meet and every single one of the lenses was marked with a paint marker like the ones used at the junkyard. Any ideas on removing it without damaging the lenses? Cant believe they marked every one of them!

Brake fluid may work. Test a small concealed area first for any bad reaction with the plastic.

goof off.
Always important to test anything on a small portion first.

Depending on the paint marker used,...I've had luck with WD-40....

Once the paint is off, polish them up with Meguire's PlastX plastic polish. I just did mine a few weeks ago. It's easy and the lenses look great.

Is it grease pencil or paint?

We use grease pencil on most stuff here. Regular rubbing alchohol works best.

It is paint from one of those markers you often see at the JY. It will come off with the wheel polish paste and lots of elbow grease. Tried that last night. I guess the up side is you can polish out the scratches and haze that way at the same time and then follow up with the Meguiars plastic polish afterward.

One way to save some time and work plus get a real good glossy finish is to glassbead the marker off and do the entire surface as well. Then clear the thing. It will gloss at least as good as new. I only use clear out of the paint gun. I've never tried the spray bomb stuff.

I do this on all my old tail lites and they always turn out good.

Easy-Off oven cleaner was always good for taking off sign paint off a truck door before vinyl became the next big thing. Used to just brush it lightly on the letters you wanted to remove, leave it for about 5 seconds or so and then wipe it off. Washed it off after with a wet rag and some Windex or some other cleaner. It always took the sign paint but never hurt the truck paint. Try it on something you don't care about first.

Kevin