Have you taken your bed off so you can see your fuel tank and the fuel pump assembly? If so, pull off the hose that pumps the fuel, not the return line, let the hose hang into a bucket then go try to start your truck. Let it turn over a few times and go look to see if it pumped anything into the bucket. My fuel pump didn't engage in a "prime" mode unless the motor was turning over. I posted this on your intro thread but wanted to answer it here incase someone else needs help also
Seems to me on the EFI engines you could jumper a couple wires under the hood in the diagnostic plug to operate the fuel pump for testing, or also by manually opening the flapper door in the AFM with the key on will engage the pump.
Air Flow Meter, its mounted next to the air filter box, the air is sucked through it from the filter to the engine, the flapper door inside swings open or closed depending on the amount of air the engine is using, the electronics inside it read the amount, temperature, ect. of the incoming air to send the info to the computer so it can tell the engine what to do.