Charging System Question

This is all 100% stock 63 wiring. No fusible links. No "direct wire" to the alternator. It's all stock. Big red runs from the alternator through the bulkhead, to the ammeter, back out the black and "wherever" it goes from there......evidently to the battery. It's not bypassing the ammeter.....it's not charging. Period. I put the meter both directly on the alternator and the battery as well. It shows battery voltage only.
OK. You said big red wire from the alt to the battery so I figured you added that. Factory alternator output was always black. Sometimes battery wire was too, except at the ammeter.
Anyway. I now know what you're saying.

Ok, I was doing that test wrong. Thanks. I'll try it tomorrow cause I'll burn the thing down in the dark.

I'd save that test for when the others strike out.
The alternator was producing power at 14.5 V a few months ago. Hard to imagine somehting happened to the wiring since then.
What is the voltage there now with engine running?
Measure the voltage going to regulator (at the IGN terminal on the VR).
If there is power there, then there should be power coming out the other side - just maybe not at the same voltage.
Jumper the VR to see if the problem is the regulator.

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