If your truck has the originally equipped 5R engine that was assemble from a kit form in Torrence, Calif. The selling dealer most likely installed either a Beam of Impco fuel system and pitched the gasoline hardware. If the engine that is under the white top cover has a doughnut shaped air filter, it is the 5R. The question still goes back to which fuel system, because the selling dealer may have install a cheaper vapor fuel system and not a liquid fuel system.