Thanks for the continued help... my truck was built in May of '67, so I'm not sure if that classifies as "late" or not... however, that almost LOOKS more "right" to me. It's a Camper Special, so it may have been wired a little different than other 67's, anyhow? That "14305 Assembly" (Connector "C")
looks almost like what I'm seeing (I have attached a picture to this post, see the circled connector). So by that, is the diagram showing there's a 4amp fuse INSIDE of that assembly?? It's so hard to pull apart, I'm almost afraid to keep trying.
Tonight I stopped on my way home at Advance Auto. The guy put his fancy tester on the battery and it came back that the battery was "Bad". I asked if that was just because it had no charge, and he said "No". He said it runs a cycle test, etc., and it has bad cells or whatever. This is the same battery that NAPA and O'Reilly have both said was good.... though I will admit that Advance's tester looked more fancy.
Anyhow, because the battery was "Bad", he went and got a good battery and plugged it up so we could test the charging systems. The tester has this clamp that he put around the negative cable that is supposed to detect the amperage coming back to the battery. It showed
NOTHING! Conversely, in another mode, it showed 0.02amps being drawn from the battery... probably by the radio. So while the alternator appears to be getting juice from the battery (via the fusible link -- verified by test light to the 'B' terminal), it does not appear to be putting anything back?
SO... I ran out of time for tonight and tomorrow. My next course of action is to remove the alternator AND the battery and take them to Advance. They will test them both again (bench test the alternator) and see if they're bad. If so, I'm going to take them to NAPA and get them replaced... the battery is an 84mo warranty, and the alternator is a 1yr warranty, I think. IF the alternator (and/or battery) tests GOOD, then I don't know what to do.
I will try to hit the regulator wires with the key on to see if I get a test light... I shouldn't expect any sparks, should I?

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