65amp wiring/trouble shooting

All 74 Valiants used the same instrument panel wiring harness, part number 3764208. The only modification made to the standard harness with heavy duty alternator was the A1D 12R which was capped as seen in the CI 5 diagram. A separate wiring harness was used with the heavy duty option, part number 3764270 which was tapped to the standard harness.

Using the CI 5 diagram as a reference, there is only one red wire connected to the + side of the ammeter. In the same diagram, two wires are shown connected to the - side of the ammeter. Actually three wires are connected to the - side of the ammeter stud.
R6C 12BK goes to the standard welded splice used in all wiring harnesses.
R6D 8BK goes to the alternator used with the heavy duty option.
C13 12BK goes to a 30 amp circuit breaker part number 3764198, which is completely separate from the fuse block. From there it goes to the heated back-lite relay. There are some omissions and mistakes in the factory service manual wiring diagrams.

Also just wondering why everyone is calling it a 65 amp option, when the parts catalog and the service manual wiring diagram refers to it as 60 amp option.