I’ve got an old tail-light lens with a clear reflector piece glued into the inside of the lens:
There is a small space between the square reflector and the lens assembly that, over the years, has leaked, collected water and turned black. Water leaks in despite the fact that the reflector is glued in to the lens assembly. I don’t want to try to remove the square reflector because I don’t want to break it or, worse, the entire lens assembly.
Any suggestions for chemicals for cleaning? Is there a product I can fill the void with that will “eat” this stuff without harming the plastic? Bleach has been suggested but I am leery that it can eat the stuff (it shakes around a bit in there when it’s dry.)