What you really want is something that will allow the truck to run for about 30-60 seconds then shut it off.
Thieves (except for the pros with a flatbed) pick a vehicle in a spot where they can work on stealing it without too much observation. If it stalls out on a roadway, they will abandon it most of the time because it's too risky to work on it there.
In the old days with carburetors, a car would run about a minute with no fuel being pumped to it before the gas stored in it would run out. Fuel injection systems need close to full pressure immediately to run the engine so if you disble the pump the best you will get is a few seconds of run time. A switch with a timer circuit to let the pump run for a short while would work good.
Steve