Deve: This is a good start for understanding and identifying what you have and, how it works. http://www.americanautowire.com/view-faq/how-to-identify-your-gm-internally-regulated-alternator/
AC Delco only but still an alternator is an alternator. Good find on the "lost" load.
Trouble shooting 101 step 1, check all connections.
Still the best and most important thing the Air Force taught me.

Steve H