There are really only two concerns to consider on Delco regulators- - - -ground polarity and current regulator setting. Adjust the current regulator to match the capacity of the generator, and press on. Those "experienced" regulators can be made to look brand new with a little dent bumping on the cover and a coat of gloss black paint. A good source of Delco regulators with low in-service hours would be the ones listed for "aircraft" applications. They don't know if the vehicle they're mounted on is rolling or flying, and the ones on Ebay are usually dirt cheap.
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
Love your enemies and drive 'em nuts!