Wiring help please

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Always tell us the year, engine, and any other relevant facts when asking a question. I infer that your is 66+ since you have the 3rd bulkhead connector for the wiper motor in the engine bay.

Some of those connections might be factory original. As I recall blk/yell are part of the front lighting. I used a 74 harness in re-wiring my 65 and recall the running lights were blk/yell wires. They are split to go from the driver's side to passenger side, plus side lights. The layout of lights changed year-year and also as the front ends became fiberglass I recall? (need ground wires then).