All the restoration Vendors sell the non stick tape that was used by the factory for you to re-wrap you harnesses.
Good to hear you solved it.

Years ago I put together my Dart Sport with a warmed over 440 etc..
Couldn't get the engine to go over 4000RPM.
All the engine harnesses were cut and taped by previous owner so I went to a local cab company that had old cabs sitting that they used as parts cars and I bought the harness out of a 318 car and modified it to work with my 440 swap.

Took the car up the block to a deserted street next to a school at night and stood on it. The car jumped up to 6500 smoking the tires going sideways to the 2nd gear shift and just revved up to the 3rd gear pull. Guys playing softball in the yard were glued to the fence and cheering, never forget that day...
Ron