The resistor and coil are just like original---except the module (Pertronix) black wire is the only wire on the coil negative(-).
So the coil runs on reduced 12 volts from the resistor --switched to ground by the module black wire--the module needs 12 volts from the switch, by the red wire. When cranking, the coil input is increased to 12 volts by the wire from the starter solenoid.
