[Andy4639]

Originally Posted by Andy4639

So what do you mean by over charged?

Here is VetteVet conversion for the SI internal regulated alternators. Use the 12 SI from the mid eighties GM vehicles. following the directions I gave, you can delete the regulator harness and the blue and white wires, although you can use them to extend the brown and red wires. Of course you'll have to use an adapter to connect the wires to the alternator.

I should have put this as VetteVet info not mine.
Mad electric is the source of all my electrical info.
How did you check the over voltage issue, with a know good digital voltmeter are the truck gauge?
Have you blown anything up in the truck? If going by the truck gauges then I would say it could be the gauge itself. You need to check it with a good hand held voltmeter.