ok, i took the foam seal out of the aluminum tank lid and i have a bunch of rubber o-rings. so i took one and put it in place of the foam seal. now when the lid closes, it snaps down instead of just closing down on the foam seal. my tank was probably a little over half full and i ran my truck for a good 5 minutes and no leaking! i guess that rubber o-ring i put in the lid sealed off the cap. i need to try it when the tank is full and see if fuel comes out around the lid again. but im still open to suggestions on how to seal the lid better.