Then yes to see if the alternator is working you want to jumper 12v to the field terminal on the alternator but it will go to full charge and high voltage. Have everything set up ahead of time. To measure voltage at the battery.
If it doesn't go to like 18v the alternator is not functioning correctly.
When you said you grounded the green field wire, did you do it at the VR with the wire removed.
If not you probably blew out the VR.
There is actually 2 fuseable wires inside to prevent a wiring melt down if the green field wire shorts etc.
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One last thing, is your alternator a round back or a square back?