How to keep Park lights on with Headlights in pre-'68 A - bodies.

Until 1968, the parking lights on US cars normally went off when the headlights were turned on. The early Plymouth Barracuda put a jumper between the tail light terminal and the parking light terminal on the plug that attaches to the headlight switch, to make the parking lights stay on when the headlights were turned on. For your Valiant, Dart, or Barracuda, you can remove the headlight switch and solder a jumper wire between the "P" and "R" terminals on your headlight switch to keep the parking lights on with the headlights.