Hy JayCone58Apache, do you have a ballast resistor mounted on your firewall, the igniton wire from the ignition switch goes to one terminal on it, and the other terminal is the one that the wire to the distributor connects to. Without that resistor and the key left on and the points closed the coil will get very hot. If I'm remembering correctly on your truck the ground cable connection is right behind the battery on the firewall, then lower down the firewall under the battery is another connection point for another ground cable to go out to a starter mounting bolt, without using these connection points the cab may be isolated from ground, hope that helps.
