Oooooooooooooops! This post is wrong. Upon further looking I think that alternator is a 10DN. These were the earliest GM alternators, first used in 1962. They DID have external regulators.

Wrong stuff here.
I'm having a hard time finding a Delco 5619 alternator internal diagram, but I'd bet the moderator's life that the alternator shown on your picture above has an internal regulator.

I'll keep looking.

Here is the 5619 from your picture.
Attachments
Clipboard01.jpg (2.01 KB, 57 downloads)

Last edited by Bill Hanlon; 08/21/2023 4:12 PM.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.