Originally Posted by snrusnak
I'm a 4th gen but my 3rd brake light was leaking, may be the same for you. I just cleaned the original gasket off(it was crappy and porous, like a sponge, no wonder it leaked) and bought new gasket material from home depot/lowes. It worked like a charm. I actually have a write up I did if you want let me know I'll post the link.
I've got a 2nd Gen and it drove me nuts. Ditto with what snrusnak said.