I measured 13.54 VDC across the battery terminals and measured 14.10 VDC between the negative battery post and the post on the back of the alternator. Any help is appreciated...thanks, Bob
Measure: between battery post and its clamp, and neg post to alt case.
You show 0.6 volt difference and should be no more than maybe 0.2 volts.
I would remove both ends of both cables and wire brush the bejesus out of them. Same with alt red wire on post AND on horn relay buss bar, and in fact, put both wires on the same screw on buss bar.
The OE ammeter is actually a millivoltmeter as the gauge is hooked up between the horn relay buss bar and battery junction block next to battery - follow red wire pigtail from clamp.
I would also get a Harbor freight ammeter, $5, maybe $10, and wire it between the battery supply wire and buss bar.
This set-up will show battery charge/discharge
Compare results with OE gauge.
Welcome, Bob, to the Club.
Just a warning, you'll be asked for pictures.