Your conversion "ain't that simple" That is because Mopar ignition switches are unique.
You REALLY need to get a factory shop manual. You can download them, free, from MyMopar
All cars, Ford, GM, Chrysler of this era, ran a resistor to the coil from the igntion switch. That circuit goes DEAD in "start" so you need "hot battery" to the coil for starting
GM/ FORD did this by means of a separate contact on the starter solenoid
Mopar did this by means of an extra switch contact in the ignition switch
INto the Mopar switch you have main hot battery power usually large red
OUT of the switch you have
ACCESSORY which feeds off to the switched acc buss in the fuse panel, this is hot either in acc or "run"
IGN1 or "ignition run." Many years this is dark blue, feeds (some years) switched power to gauges and warning lamps, and goes out through the bulkhead connector to feed the ignition system, the VR / alternator field, electric choke if used, etc
START--Many years yellow, goes from key out through bulkhead connector to start relay
And the trick one, IGN2 many years brown, the ballast bypass circuit. Again, in "start" IGN1 "run" GOES DEAD. Only "start" and IGN2 are hot---and they are different contacts to prevent loop/ feedback. This wire goes out through the bulkhead to the coil + side of the ballast resistor
HOW TO GET AROUND THIS
You need a source of ignition power in "start" You cannot use the "start" wire directly, but you CAN add a second (like a bosch relay) to the yellow "start" circuit so that the new relay and the start relay key up together. Then run power to the relay, and run the switched contact to the old brown connection.
Another way you could do this is to buy about a 10amp 50PIV or 100PIV rectifier diode and wire it from the yellow start circuit to the old brown circuit. Diodes have a band on one end to denote direction. You want to hook this band so that it is towards the brown going to the coil and not the yellow start circuit
Here is your connector, straight out of the 72 service manual
View attachment 1715759213
If you use a diode you want a silicon rectifier diode. What is thought of as "electron flow" goes from left to right. The right side in the drawing goes to the old brown, and the left side in the drawing goes to the yellow on the key
What they are calling "current flow" is NOT how I learned electron theory
View attachment 1715759214
