NO matter how solid and rust free your Camaro is, there is always the Achilles heel, or the rear window area. This car probably had a rust hole for some time as I noticed water stains on the package tray. What did the original owner do to solve the problem? Add some silicone, some more silicone, and some more silicone. That will surely stop the water! The rear window was never removed from the car. They just siliconed everywhere between the sail panels and the glass. Needless to say water still came in near the roof and dripped down which made matters worse because the water couldn't evaporate. After some welding and a few patch panels it's back to being rust free