OK well what regulator do you have? If you have the once popular Mopar race regulator, you wire it like a pre 70. In other words GROUND it, the ign lead goes to switched 12V AKA key, "ignition run" and the field lead goes to either field connection on the alternator. Ground the remaining field connector
This one below
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If you have the "flat" electronic one built for 70/ later, and they make (d) a race version of that also, you wire the middle terminal of the VR to switched ignition, the far right terminal to either field terminal and of course ground the VR.
Last, you take the remaining alternator field terminal and wire it to switched 12V
Like this
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