From SNL-G-508 pages 181-187
Installed on CCKWs 87614 through 384577 (May 42 through Nov 44)
6V 40A Negative ground. This was the 'standardized' electrical system the Army settled on for most vehicles. There were POSITIVE ground, 6v 20A generators and regulators (used on pre SN 87614 CCKWs) but they were phased out and upgraded as needed. These are considered 'sealed' units as there are gaskets in place to keep out moisture. The screw post on the 'BATTERY' side has a hole for a lead seal to be installed. That post is also *slightly* longer, also.
Satin black color outside.
zinc chromate (like a lime green) color inside.
Data plate is zinc with black print.
The notable thing is that there are only two captive knurled nuts on opposite ends of the regulator. The SNL does not clearly show them, but they are stamped in place and do not come out.
The terminals are marked from left to right 'Battery', 'Field', 'Armature' on the insulator. They are filled with white paint to stand out.
Bottom is unpainted. If you look at the rounded edges you can see the red primer in some spots.
The all important data plate. Delco-Remy and stamped with various settings like voltages when relays are to open.
TM9-801 has more detailed operational information. Section XXI Para 116 'Generating System'.