gas started pouring out

[jessemonroe]

Ok filled up tank and gas started pouring out from fuel pump...need advice and how hard is it to repair?

[HenryJ]

The fuel pump is in the tank. If you mean the ring that retains the pump/sender assembly, it is just a rubber seal and should be an easy fix. Too bad the tank is full. Draining the tank prior to dropping it is no fun.
Make sure it is not a cracked filler tube connection. That is pretty common. It requires tank replacement.

[jessemonroe]

I think your right on the rubber O-ring. When I topped it off you could see between the bed and the cab and the gas came out where the sending unit/fuel pump is.

[HenryJ]

It may be bunched up, but more likely is that the ring is "crossthreaded" Not line up flat and turned in a parallel plane.
Dropping the tank is not a big deal. While you are there, look for a manufacturer identification on the pump and look to see if the wires have been cut to change the connector. Delphi and spliced wires is a good thing. Carter means you will be dropping the tank again when it fails. That will be sooner rather than later.