My 1966 Polara died on side of road last Friday and had to be trailered home. After installing new #4 ground from engine to chassis, #8 plug wire, fuel filter and charge the battery the car will start and run well until it starts to warm up and then die. I replaced the ecm with a spare and got the same results. The ballast resistor is showing about 12 volts in and 9 out when the ignition is off and 13.5 in and 12 out with the car running. The engine sounds strong when fast idling but dies. Can anyone point me in the right direction. Thank You, Bruce.