If the truck runs, there is no need to bleed the valve. If the truck ran out of fuel, you can crank it some while pushing the schrader valve and it will speed up the process of getting rid of the air in the fuel filter. It also verifies you are getting fuel. Once it starts spitting fuel you can quit pushing it open and then keep cranking off and on till the fuel finally gets to the injectors.
The fuel selector valve is on the inside frame approximately under the drivers door.
I can't recommend an electric fuel pump unless you have a special reason to use one. People have so many problems with them and seem to have a hard time finding one that will last. The mechanical pumps seem to last a long time.