Over charging

Keep in your mind how simple the system is. THE PATH

From the key, the "ignition run" wire runs out into the engine bay. THAT wire supplies ignition, VR, and alternator field. So a simple circuit, it supplies "everything."

Blue from the key goes to the alternator field, through the field, and the VR, via the green, controls "the amount of grounding" so to speak, to control charging.

VR gets power from the same blue circuit, ground, and the green from the VR goes to the field

MOST POPULAR cause of overcharge is bad VR or shorted brush holder at the alternator. DISconnect both field wires at the alternator. Check continuity to ground at the brushes. Should be open / infinity to ground.