65 Barracuda electronic ignition, orange box, ballast resistor questions

What I had said in part is that there has to be a matching connector for the distributor

The triangle one you showed is for the 70 and later VR. That must use a 70 and later alternator with the two field connections, properly called "isolated field."

I have no idea why they have the dual connectors for the 4 pin ballast and yet supplied a 2 pin ballast. Maybe the harness is simply supposed to be compatible with a 4 pin ballast and 5 pin ECU

5 pin ECU must use a 4 pin ballast

4 pin ECU can use either 4 or 2 pin ballast