Please do not replace anything until you do some troubleshooting. Likely the LAST things you need is either a VR or ballast
You need to do some "stuff"
1...Wander over to MyMopar and download the 72 Plymouth service manual, which is FREE Also download from the wiring section, the 2 page aftermarket wiring diagram. These are not always as detailed or as accurate, but can be easier to follow
2...If you do not have, get yourself a basic multimeter and a 12V test lamp, and either some alligator clip jumper wires or at least alligator clips to make a couple.
Next, read this article. You do NOT need to do this "mod" necessarily, but read the article so you are aware of the why how and what. And there is a nice diagram there of the main power distribution in these girls
Catalog
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