Mel,
In your latest post you are wondering about a 12 volt conversion for your
Ford. I do believe 6 volts will work just fine and from a distance to eliminate the
possibility of a coil issue consider installing a NAPA coil pt# IC-7. This coil does NOT require a resistor so one potential problem is eliminated. If you do choose to try this
approach remember if your Ford is still positive ground the positive side of the coil
( plainly marked )is attached to the wire coming from the distributor, The negative side of the coil is attached to the hot wire coming from the ignition switch.
I'm certainly not a fan of off hand parts changing but ,again from a distance, it might
be worth a shot.
If the car starts and runs well until hot I guess I'd leave the distributor out of the
equation right now.
This is only my assessment based on information supplied, I respect any and all other
inputs.
Charlie ny