The first thing I would do is ELIMINATE the truck wiring system. Make a 12g jumper wire to run from battery + to coil +. If spark color improves or if it fires and runs good then trace down the trouble. We also have a freon jug gas can with a regulator so pressure can be set from zero to 150psi to cover both carbs and fuel injection. This eliminates the factory fuel system to isolate the trouble if there. KISS
