Look at the diagnostic connector under the hood where codes are pulled. There should be a tan wire with a green stripe. Run a jumper wire from that terminal to ground.
You should hear the pump run and the truck should start if this is a lack of fuel problem.
If the truck does run then disconnect the jumper wire. This means that for some reason the fuel pump relay is not getting a ground through the ECM.
This could be caused by a faulty TFI ignition module, faulty ECM, etc.
If it does not run then it's very well could be a faulty pump relay.
Take a test light and connect it to that tan/green wire in the diag. connector. Turn the key to the RUN position. The light should be on. If not, likely a faulty ECM circuit.
If the light is on, crank the engine over a bit. After 3 or 4 seconds of cranking the light should still be on. If not, a likely TFI module problem.
(I should have added that pulling the codes might not be a bad idea just in case there is a loss of PIP code; this being the signal the TFI module sends to the ECM which then triggers the pump relay based on that signal.)