Has anyone utilized an A-circuit externally regulated alternator in a B-circuit configuration?
B-circuit field is switched on positive + side of circuit i.e.1969 and earlier Mopar.
A-circuit field is switched on ground - side of the circuit i.e. 1970 and later.

I would like to install a late model Dodge alternator (A-circuit ext reg,) into a 1969 Plymouth with the factory harness and regulator.

I figured to simple ground the field circuit at the alternator and wire the positive field lead into the pigtail.

Thanks.

never heard it called that, but it is what I do.
I have a 65 coronet, using the single field voltage reg, using a 2000 durango alt, so dual field.
previously I did the same using the 89 m-body 73amp alt using the single field voltage reg as well.

as you say, ground 1 of the fields on the alt, wire up the other field from the vr like normal.
been running that way for years.
I did have to clean up the sensing line voltage at some point, as it was overcharging, but it was due to the voltage drop across the bulkhead connector.

Just need to ground one of the brushes


2 options for that!

Get a ground wire jumper to one of the brushes

Replace the screw mount isolation washer of the brush for a metallic one. This will ground the brush without an ugly wire around


BUT if using second option, clip off, bent or seal the brush prong you are grounding to prevent from conect accidentally the field wire there or will short out as soon you put the key in RUN

I agree with the suggestions. The 'A' and 'B' descriptions are accurate but not commonly used in the field. Another way to look at this is the 'B' configuration is a grounded field and the 'A' configuration is an isolated field.