My gut says fuel delivery problem of some kind, but it could be fuel, air or spark. My truck was doing similar things right after I got it back on the road. Turned out to be a dead yellow jacket that had been living in the fuel line or gas tank. It would travel as far as the filter and get hung up on the edge of the filter's inlet, but still back in the rubber line. From the look of things, it would get jammed in the filter inlet, cut off fuel flow, then after things sat a while it would move back a little and everything seemed to work again. Only reason I found it was because I pulled that line when I dropped the tank to replace the sending unit. Even dead those little suckers can sting ya one way or the other.
If all the vents were plugged on your gas tank, it could be creating a vacuum inside. Once it gets too bad, the pump can't pull gas against the vac inside the tank. Get the problem to show itself, hop out, and pop off the gas cap. If you hear it suck air in, this might be on the right track.