For a write up follow this link https://www.backyardmechanic.org/how-... This can be used when the computer/ECM stops regulating the voltage. This can also be done to regulate any 12 volt battery alternator combination. It completely separates the voltage regulating from the computer . Here are the parts I use. A junk yard would also have these parts.
Parts used Dodge external voltage regulator (1971-1989) Voltage Regulator Connector 14 Gauge wire (I color code mine red, black and green for a good ground) Inline fuse with 15-20 AMP fuse (Not necessary but what I do) Screws Electrical tape Wire Nuts (I solder the connections together but some people use wire nuts.)