65amp wiring/trouble shooting

To wit
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Based on what we see on the example in this thread, it appears the factory left as much of the standard harness in place as they could.
For example A1B 10R and fusible link A1C 16 DBL could have easily been removed, but it wasn't.

Therefore if I had to guess, following that logic they would have left R6C attached to the ammeter stud. The heated back light feed therefore would be the one spliced into the alternator output line R6E
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Easier to follow when laid out like this.
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Best to verify on the car!

IMO it is worth the small effort to verify for two reasons.
1. If the voltage issue has not been resolved, knowing the current path will make it possible to track down the location(s) of the resistance.
2. If questions arise in the future, either on this car, or other similarly equipped '74 models, it will save a bunch of time.

3. If someone is looking for replacement parts, they will know what to look for. Specifically how the '74 version may differ from the '73 etc.