Apart from a full day at the office, my time was spent in trying to sort out the alternator issues.
I first got my trusty Dremel tool out of storage and spent time in the cramped confines of the engine room drilling a slot into the stripped screw. That done, I finally got the small screw out and could remove the regulator. This unit also held the 2 brushes for the rotor, and they were in order and within specifications. But measuring the regulator with the power supply and my multimeter didn’t go as easily as I’d hoped; my power supply is for electronics and only goes to 20V.
The regulator is designed to limit the output voltage to around 28.8V. If the voltage is less, it gets passed through. If the voltage is higher, the output is regulated and essentially turned off. At 20V it was working as expected, and I hooked up my solar panels which produced around 40V, and the output was turned off, but the critical voltage range between 24 and 29 couldn’t be tested.
I also attempted removing the alternator again and got the 2 big holding bolts removed but could not budge it. I opted to stop trying to remove it, since I was worried that I wouldn’t be able to put it back in and since the alternator is need for the belt system that also powers the 12V alternator I didn’t want to risk that.