Obviously there's a change in the alternator wiring from old to new. What was the new alternator originally used for? I'd find out what car it was intended for and compare wiring schematics between that & your specific year Pantera. And as I remember it, the small wire goes to the old regulator which then had 4 other wires connected at various place thru the molded connector. Did you get directions for installing the new conversion alternator? I don't believe they are plug-&-play.
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