I started up the Dodge with my DVM in hand. I measured the voltage on each of the 3 studs on the back of the alternator with the alternator not working and then when it was working again relative to ground on terminal A. I should have measured between B and C as well.

Update: I had terminals B and C mixed up. So I changed them in the table and also added a pic that shows the green and blue wires going to the alternator.

Working    Not Working
B 14.0v         11.1v
C 6.5-6.8v     1.9v
D 14.5v         12.2v

All I did was wiggle the black connector over on the passenger side inner fender and it started charging again. It is possible however that the brushes are just worn badly. It looks like I might get that ND shield off of the back of the alternator and that would allow easy removal of the brush assembly for inspection/replacement.

Here is a rear view of the alternator. The two studs on the right are the field connections. The one at the very bottom with the plastic shroud around it is the output wire that goes to the battery. The voltage drop from that stud to the battery’s positive post was 1/4 volt. So it’s ok. The ground from the alternator to the negative terminal of the battery was about 1/8 volt.