Built In Ballast Resistor In Ignition Coil

66plyValiant said

the ECU itself sees battery voltage, its only the coil that is regulated by the ballast to the tune of 6-7 volts when running and battery voltage when cranking, you can remove the ballast if you put a hotter coil on

you are correct, all makes used a form of resistance to lower voltage for coil but its not needed to protect ECU

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I have not read that a Mopar ECU can drive a hotter non-ballast coil. One could try that, but you may find melted epoxy running down your inner fender from the ECU. Even my after-market Crane XR700 ECU says to use a ballast with the coil, as I understand the original Pertronix Ignitor also requires.

The earliest Mopar ECU's also needed a 5 ohm ballast for the ECU supply. Those had the 4-pin ballast. The other ballast was ~0.5 ohm for the coil. I think the 2-pin ballast was the same ~0.5 ohm. You can't accurately measure 0.5 ohm with a multimeter, and the resistance goes up greatly with temperature, i.e. in use. Better to rely on getting the correct PN for your car.