Alternator wiring 66 Dodge Dart

OK that alternator is a later model known as "isolated field" and often incorrectly called "dual field." That started in 1970 with the electronic regulator. By adding one wire you can convert from the old 66 style wiring/ regulator to the 70 and later electronic

So you have two options

1....If you have a good VR that belongs on the 66 (pre 70) you can ground either of the two field connections, connect your green field wire (from the VR) to the remaining field, and of course the black no 10 output wire to the stud. I have no idea what might be spliced in

2....By adding a second "switched ignition run" wire, that is 12V that comes alive from the key in "run" and run that to one of the alternator field connections, you can then convert to a 70/ later electronic regulator