I thought my 71 had the wrong headlight surrounds so I purchased the correct white reproductions. Once I took off my black ones I noticed someone had painted over the original ivory ones. What is the best way to remove the black paint without damaging the original color? Thank you.Click to view attachment

I’ve tried to remove black paint from white headlight surrounds but never got results good enough to live with. I’ve always had to paint them afterwards.
It was quite common for people to paint them black.

The only thing I would try is walnut shells in a media blaster, but you’ll probably have to paint them white

I would try using Easy Off brand oven cleaner. Spray it on and leave it for a few hours, then rinse it off. It won't damage the plastic; I have used it to remove paint from old scale model slot car bodies painted in the 1960's. Obviously, don't put the plastic parts in the oven; just use the Easy Off at room temperature.

My wife just tackled this over the weekend while I was replacing fuel lines. She tried a few things like Goof-off, but found that acetone worked best. I was worried it would melt the plastic, but after testing it seemed fine. They were both blue. Still need some work, but the blue paint is off. Probably go to bleaching next.
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There are quite a few threads with many different approaches! Search and ye shall find:

• Restoring white headlight surrounds
• 1970 914-6 headlight surrounds