Voltage Regulator Grounding

Grounding the alternator's external voltage regulator to the engine block,
in lieu of the alternator's ground connection, is a more efficient way to
charge the batteries because it eliminates the problems associated with the
electrical resistance inherent in the mechanical connection between the
alternator and the engine block. Whew, that's a mouthfull ;-)

Here's a real-world example. With Nellie's engine running and the batteries
charging, the voltage between the battery's + and the alternator's ground,
aka the regulator's sense voltage, is 14.2V. However, the actual voltage
between the batteries + and - posts is 13.7V. Hmm, this is a problem. We
need the sense line to measure the battery's voltage, and it's not. The
voltage difference results in significant battery undercharging. By moving
the regulator's ground from the alternator to the block, the sense and
battery voltages will be the same.

Bottom line, I'm moving the voltage regulator's ground from the alternator
to the engine block.