Wiring has not been tampered with according to the same owner since 1973. Unless the car had re-wire done in it's first 2 years... We've tried to match up the diagram with what we are working with to the best of our ability, but the colors are still different and in many cases, the color combos we have here are un-accounted for altogether on the color abreviation legend. We're trying to track down a Mercedes tech binder for 1971 280SL that were given to and used by factory techs, but that's like finding a needle in a haystack!