67 Dart electrical problem

That would be my assumption as well. BUT you should refer to the Protronics wiring diagram for what gets powered from where. 67dart273 does a really good job outlining the test procedures.

I pulled up a random pertronix install sheet. What part number are you using?

This link takes you to their FAQ and install sheets.
PerTronix Technical Help Desk

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I think it's 1381. Distributor wires are attached as in diagram, ballast resistor bypassed, and using pertronix coil. Ran great before trouble started. Replaced old pertronix with identical new one because I thought it was failing but made no difference.