1967 Fastback Wiring Harness

I think the assembly drawings will be helpful for your project.
One cause of electrical problems is improper routing and support. Its really common to move wires when working on a car and not put them back. (guilty as charged) Or in your case there's nothing to reference because everything was removed months ago. Without support and strain relief, eventually insulation gets cut or chafed, and connections get strained and weakened.

Assembly drawings:
My review of Faxon book, 1967-1969 Dodge & Plymouth Body & Electrical Assembly Manual

There's basically three harnesses:
Engine and Headlight.
Dash-Instrument Panel (orignal part number is on the harness by headlight/ high/low switch connector)
Body (goes to interior and tail lights and fuel sender)

Originally seperate was the fusible link (will be included with most repops), Console if present, A/C if present, reverse switch harness.

Example of practical application of assembly drawings for restoration.
Headlight grounds

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