Just replaced my fuel pump by cutting a trap door in a 96 firebird ws6. When I was filling the tank it would leak slightly then stop, it also leaked about the same once it turned back on as well. I pulled my trap door back up to see if it was coming from the top of the fuel tank but it was bone dry, reason I know is because the shavings from the metal I didn't clean up were still there. I've checked the filler neck through the gas door but it doesn't seem to be leaking. Mainly coming from the drivers side just to the left of the tank. Any help is appreciated, thank you.

 

The gas will evaporate instead of remaining damp. You may still have a leak at the top of the tank where the pump slides in. It's probably leaking while you're driving and the pump is running, and then drying out before you get your access panel open.