I doubt it being your lift pump. Your lift pump COULD be dead, but if it was, it wouldn't cause the truck not to run.
The only thing a lift pump will do is kill your injector pump. My vote is for the VP44 injector pump.
Try this: Go out and get in your truck. Bump the starter, but do NOT let the engine fire. Just bump it maybe twice. Ok, now pop the hood real fast and get out. Hold your ear sorta by the fuel filter and listen. Do you hear anything?
There is a small pump down there mounted to the side of the block. That would be your lift pump. When you bump the key, the pump will run to prime the fuel system. IF the pump is good, it's usually loud and can be heard easily. If it's bad, you'll BARELY hear it, or not at all.
You'll likely need a new one, or better yet, a FASS
and a new VP44 pump.
I reccomend getting some gauges too. ATLEAST a fuel pressure and Pyrometer gauge. Boost isn't really needed until you get to pushing major HP, but since a boost gauge is relatively cheap, you might as well get one of those too.