Dear CK:

I can't say anything about water leaking into the trunk. I has problems with blowen brakelight bulbs after heavy rain or car wash. I think one cause of the problem is the old "cursion" around the tail light assemblies, which is made out of sponge type soft material. It gets harden when the car gets old, and water seeps through and gets into the tail light cocmpartment. One solution, which my mechanic did for me about 7 or so years ago, for preventing repeated brake bulbs replacement is to drill small hole at the bottom of the brake light chambers. He drilled 3 holes about 1/8" in diameter on each side to drain water. I haven't had any problem ever since. BTW, those plastic cover can last for a very long time.

Joseph
87 760GLE 191K