Voltage issue - Gauge Cluster and wiring Questions

[FirstOwner69]

Originally Posted by greywurm

So I got everything hooked back up. Replaced all of the twisted splices with butt connectors and cut the alternator wires back behind the melted areas. Added the black fused wire near the passenger side headlight to the junction for the positive terminal of the battery.

Voltage at the battery when off is 12.35 volts, same at alternator.
At the battery while running, 12.14
At the posts on the alternator, 12.04. I am touching the leadsto the black and red posts
When I turn the headlights on, it drops 11.97 at the battery and 11.71 at the alternator.
I am still experiencing .01 volts dropping every 30 seconds to a minute or so at idle.

Anything else I can do to troubleshoot?
I am done messing with it for the day.

You mentioned that you also replaced the voltage regulator. I'm starting to wonder if it or its wiring is defective. If defective, it could explain these symptoms. From one of your first pictures, it appears to be a newer type solid state unit. I seem to remember a thread a couple years ago where someone had a slow voltage drain with one of these such as you've described.