Does anyone have the original and minimum diameter of the commutator for 57 Tbird generator? 

The generator is charging again.
Voltage was a bit high, so I had to adjust the regulator.
The job was more work than it should have been. Sometime in the past the rear bolt was put in from the block side and it would have been bolted on with the bracket to the timing cover. So I had to remove the mounting bracket to get it off. That's when I discovered the bolts go through to the water jacket. 😒So drain the coolant and clean up off the floor. LOL
Not sure why Ford made it so tight against the block and head. Quite a squeeze to get a nut on the bolt when I put the gen back on. I had to tape the nut to an open-end spanner/wrench to hold it while turning the bold into the nut. Even the rear terminal will hit the head if you try to swivel the generator up.