73 swinger 318 will start run drive. gets to temp dies

The coil has no physical ground on it per se; the mounting is only a physical mount; no ground on/to the coil body. Hard to say if it was damaged by the looseness or not...is it dented or punctured where it was loose?

- How is the grounding on the ECU to the body? Super clean or not?
- Check all wires in and around the ignition system
- Put in a new ballast resistor (cheap and easy to do)

Take a voltmeter with you.