If your car has a Prestolite alternator and you are in need of a voltage regulator, you will find the original Prestolite #VBV6221A three coil regulator hard to find.
With slight changes you can use a Chrysler product unit, 1961-1968 after market #VR706 that can be found at most all auto parts stores.
First, disconnect the battery. The old regulator will have four terminals and the replacement will have only two, one spade type and one screw type. The screw terminal is the field wire (normally white with a black tracer),connect as normal. The other terminal wire will need a spade connector attached to it, ( from the "I" terminal, normally yellow with black tracer). Connect to the spade terminal of the regulator.
You will have two wires left from the "A" and "B" terminals of the old regulator. (these would have voltage if the battery were connected!) Solder these two wires together and tape for insulation, (normally these wires are white with red and a solid black).
On Avantis do not forget the ground wire on the mounting bolt.
Now reconnect the battery