On my '73 there is a component that mounts on the manifold that gets power from the ignition & sends power to a heater in the choke coil to heat it. I checked the diagrams at mymopar.com & it is spliced to the same wire that feeds the ballast resistor, the '71 diagrams did not show this but it was apparently for a non-electronic ignition. If you get 12V with ignition on & none in the off or accy. position it should be good.
