I have bypassed the ballast resistor completely after installing a pertronix system. I used a fuse to connect the two wires together to complete the circuit.
One more type... OEM coil was not designed to receive 12 volts full time. It gets 12 volts on one wire during start, lesser volts from another wire routed through a ballast resistor in run.
When a OEM coil overheats it causes stumble and shut down. Worst case scenario , it leaks a oily mess and/or becomes a fire hazard. Good luck to all