Alternator

If the correct terminal is what you have found, it is low and it will cause overcharging. I need a link for the destructions to whatever your ignition is, and how it's wired.


Forgettting the Hyfire for a moment, let's consider "factory." Whether you have a 2 or 4 prong resistor, the factory wiring is the same as the diagram I posted. That is 1/2 the 4 prong resistor is the same as the diagram above

That diagram does not show everything, but look at the top of the ballast resistor. If you have a 4 prong resistor, that will be the end of the ballast which is jumpered together.

Now, the PATH of that part of the circuit is as follows:

From battery -- to starter relay stud -- fuse link -- bulkhead connector -- ammeter circuit -- ignition switch connector -- through the switch -- back out the switch connector on dark blue "run" wire -- back out the bulkhead -- and to the ballast resistor.

Now ANY point in that path listed above, or MORE than one can be a cause for drop. It goes through the bulkhead connector TWICE -- once on the way IN from the battery, and once coming back OUT from the key, on the dark blue. IF THAT is the wire you have found, you need to fix the problem, or you will have overcharging issues.

Photos of what you are up to would help