I cant seem to find the Ballast Resistor (Or Ignition resistor) on my 92 W150. It is supposed to be on the firewall but all that is there is a large connector with all the electrical running into the firewall to fusebox? Is this part even on this truck? My Haynes manual shows it on the truck but all I can find is the big plug connector. Also I hooked up a ignition tester to my plug wires and no spark is present. I am assuming this means a possible distributor problem? ( I have already replaced the plug wires, cap and rotor) My truck has the camshaft position sensor on it so I dont have to worry about timing. What else could it be???