Stop Fuel Leak

guys,

replaced my fuel tank during my restoration and the tank filler neck seal.

a few weeks ago i put about 20.00 ( little over half tank ) worth of gas in it and proceeded to get a leak around the new seal.

manually removed about 5 gallons and the leak stopped.

Is there anything that i can use to seal this location that will not leak again or ??

makes me wonder if the location of the filler tube hole may be off since the tank is a repop.

Thanks for you suggestions and input.

Bruce