I had the floor pans replaced on my 82, and the sound deading material by the pedals was wet. My dad noticed there was some area by the firewall(maybe on top, where the drainage for the windshield is) that looks like it wasn't caulked from the factory.

I haven't seen the area, but I find it really odd that it's been doing this for 23 years. The car was in storage for a bit during the early 90s.

Anyone have this problem, or any imput as to how or why this happened?

i have the same problem whit my 83.The yellow insulation stuff was all soaked on both side so with time it rotten the floor pan.I think that leafs get stuck under the windshield grill and it made a hole in the firewall.i'm not sure cause i havent removed it yet(PITA),

Hope this help. RON