Alternator wiring using C5/C6 Corvette Alternator

[gnvair]

You want to run a volt gauge? Not the warning light?

Yes, my car has the factory gauge package. It does not have the warning light.

 

[ELCAM]

Sounds like you wont need the brown or red wire just the control wire coming from your computer.

 

[gnvair]

I did some more research using the 1978 Chevrolet wiring diagrams.
The brown wire to the original wire (#25) is feed, voltage regulator controlled.
The other red wires are #2 in the diagram and go directly to the starter.
As for the voltmeter gauge
It has 2 wires.
First is #39 pink/black which is feed, ignition switch on and crank. All of the gauges are powered with this same wire. The other wire is #150 black which is the common ground for the entire cluster.
So, my conclusion is the gauge gets its voltage reading from the pink/black wire. Nothing at the original alternator has anything to do with the voltmeter.
The Corvette alternator needs 1 of 2 wires to terminal/pin B. With the Chevrolet Performance harness that would be the orange wire which is Generator Pos B. If I wasn't using the Chevrolet Performance harness, then the original brown wire would go to that terminal/pin B.
So, it looks like I just need the orange wire at terminal/pin B and I should be good. The original alternator regulator plug and wires can be removed.

 

[ELCAM]

It sounds like you have it figured out.

 

[gnvair]

It sounds like you have it figured out.

Yes, I believe I do. Thanks to all who assisted. I appreciate it.

 

[78Delta88]

Yep, that's the correct connector.

The unit self excites at 1200-1400 RPM.