Try connecting a jumper wire from a known source of battery voltage such as the big main battery lead at the alternator to the "field" terminal at the 2-wire plug in the back of the alternator. This bypasses the regulator and puts the alternator into full output. "New" is not necessarily "good" where those 4-pin extrnal regulators are concerned, particularly the new design solid-state ones without the magnetic contact points inside.

No, that vehicle would have an alternator as original equipment. The 42 amp alternator was one of the earliest ones. They quickly increased the capacity to 65 amps or more.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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