Hey guys,
I am about to put my sub box in my trunk, but before I do, I must put my spare tire back in and put all my panels back on. But I noticed a water trail running from where the bottom bolt of the bumper cover bolts up to the actual unibody/quarter panel. Its running underneath. I've checked this with water when it was dry out, and its not the weather stripping on the trunk at all. The water runs off of the pass tail light, and down the flange and into the compartment to drain out the little hole in the bottom of it. I want to know whats the easiest way to fix this without having to worry about rust. Should I put body filler in the INSIDE of it to seal it out, or will that rust it on the outside because of water sitting IN the crack, theres no way to get to it underneath the car. any Ideas...

 

It might not be the seals themselves, but there's a chance it's the silicone seal between the hatch glass and the deck lid.

There should also be some foam-like seals for the holes at the taillights.

 

I know, but water is running down the flange from the water that runs off of the tail lights ( I have a camaro, which has the slanted side tail lights that allow water to run into the flange thus making it into the compartment. I've checked the seals, they are good