65 barracuda not charging PLZ help

Murray said
What do mean "one of the Field posts are cut"? One of these is grounded by a screw, not by being "cut

Isolated field alts (typically square back) converted to single field wire have the grounded field wire terminal clipped off so you can not accidentally put the field wire on it and short out your VR.

Note clipped terminal in the 7 to 8 o'clock position