Sounds like a problem similar to the one I have been working on. You should be able to unsnap the cover on the fuse panel on drivers side and the fuse size and description are molded into the cover. When you disconnect the starter at the solenoid (so you can hear what is going on) and turn the key on to the start position you should be able to hear the fuel pump you have selected (front or rear) Then you need to follow the wiring to the very back of the engine to find the oil pressure switch (you actually should find two and the one you are looking for is on the drivers side of the truck)which controls the power to the fuel pumps when the engine is running. You can unplug the connector to the oil pressure switch and jumper it out and the you should be able to hear the fuel pump running when the key in in the run position even when the engine is not running. If the fuel pumps are running in both situations you should be in business. As you probably know the excess fuel is routed back to the tank whenever the carb bowl fills up. Good Luck!!!!