I posted a question regarding removing a line on my deck lid from the convertible 1993. The suggestion was simple green to remove the line. I will never use simple green on this original paint again.

 

Best to always try something like that on a area that is not readily seen to prevent what happened to you. Since Simple Green is just a high-powered surfactant, not a solvent, I'm not sure how it could affect paint. Usually marks like that can be polished out with a very fine polishing compound.