Ok, so here are my findings:
I connected an external voltmeter to the battery directly. Readings were pretty much the same as my wired meter; usually about half a volt higher. While running the bike, RPMs made no discernible difference in the readings. However, there were a few distinct "clicks" that would occur every so often where the voltage would go from nominal battery voltage (around 13v) to 15+ (as high as 17 today!). The lights would get brighter when that happened too. But then, sometimes after a minute or so, there would be another so-called 'click' and the lights and voltage would drop to normal again. By 'click', I'm not referring to an audible click, but a visible difference in the voltage and lighting. It's possible there was an audible click too but it would be hard to tell with the bike running.
Installing the LED headlight must have been coincidental to this voltage behavior, because I swapped in the halogen again, plugged the relay back in with no effect.
I had just put in an AGM a short while before the LED but that wouldn't make any difference either, would it?
Moving along, I then unplugged the wires from the R/R to conduct the resistance tests, as outlined in Clymer. The first picture is from the manual, showing the various readings from terminal to terminal. The second picture shows my results in the same format.
I confess that I am not very savvy doing resistance tests. What I mean by that is that I don't have much idea what I'm doing. I know the probes need to be clean and tight and that the meter needs to be set to measure resistance. My new digital meter automatically changes scale depending on the readings, so that's supposed to be easier I guess but is also more confusing, at least to me.
I am hoping some of you can help me interpret these readings. None of them are what the book calls for but at least a few seem pretty close. One thing that definitely stands out though is that the "M" terminal consistently does Nothing (hence the "N" in the table). It never registers anything no matter what I do. What does that terminal do and what does it mean when it's dead?How about the other readings?