Gasoline is well over three dollars a gallon. (FJB) Higher still depending on geographic location/state taxes. I was paying over five bucks a gallon in California about this time last year.
"I" would try "priming" the pump with the fuel filter disconnected on the inlet side. Pump runs for two seconds--collect the fuel in a suitable container for inspection. See if you get water...or gasoline. If gasoline, reconnect the filter, see if the engine runs. If it runs...I wouldn't drain the tank except by putting miles on the truck. As long as the truck runs OK, don't change the fuel filter until the tank has been re-filled at least once, but probably not more than two or three re-fills.
The absolute worst thing you can do is to spread the fuel on open ground, or let it "evaporate" off of pavement. Set fire to it one way or another--in the combustion chambers of the truck, in the combustion chamber(s) of a lawn-mower, or in a burn-pit after mixing with some Diesel, Kerosene, or used oil (so it's not so explosive.)