Can a HEI coil trigger a Mopar ECU?

You can put an HEI module right where the Mopar one is. In fact a few guys have gutted a Mopar box and mounted an HEI 4 pin inside the box. If that is what you are doing don't screw around trying to use both. Pick one or the other. The diagram George Jets posted was created by a member here from my henscratching. "It works"

A good quality HEI module is likely a lot more tolerant of heat than a Mopar one is. That's because they were mounted IN the distributor on a HOT engine!!