I have a1973 Ventura with wiring problems.
Car has been restored , but I have multiple light problems.
Agree with Js08016. The wiring on that car is relatively simple. About the most complicated part is the turn signal/brake light setup. Make sure you've got a solid ground at the lights that are failing, and just trace each wire backwards. If you're trying to keep the car factory-authentic it adds a bit of work for you. Tracing electric problems can be time-consuming, no easy fix. Good luck!