The original-equipment Delco regulators were polarity-sensitive. Most aftermarket replacements work on either polarity. Some of the internal wiring is slightly different on positive VS negative ground regulators- - - -but I don't remember the difference at the moment. Usually, the regulator housing will be stamped to indicate pos. or neg. ground, or the part number will be different. GMC truck regulators would be the most common ones with positive grounding. I'll see if any of my reference material can explain the difference. Are we dealing with a 6V system?
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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