This pic shows three styles of Model A, B, and Model 46 water inlet castings. The one on the left is the typical Model A casting A-8275-A. The one in the middle is the typical Model B casting B-8275-A, which is physically identical to the A-8275-A except for the part number prefix cast in. The carryover A inlet was renumbered and given the B prefix in 1932, and was used through the end of 1934.
The casting on the far right is the very unusual B-8275-B, which has a different inlet angle in both the front and side view compared to the standard casting. It is also physically identical to the A-8275-B, not shown. This Special Equipment casting was used with the long high output generators released in mid 1931 and was used as special equipment on both Model A's and B's. This casting was also used with a special radiator outlet pipe which was longer and had a sharper bend at the rear.
Per the Ford detail drawings at the archives, the standard A-8275-A and B-8275-A inlets have a 25 degree angle in front view and a 57 degree angle in side view measured relative to vertical.
In contrast, the Special Equipment A-8275-B and B-8275-B inlets have a 27 degree angle in front view and a 37.25 degree angle in side view. The B suffix inlets have the hose connection more upright and vertical and pointed more outboard, and are used with a longer water pipe having a sharper bend at the rear.
This pic shows the detail of the generator harness wire clamp boss. Note the rounded boss on the right hand inlet. This boss shape is characteristic of the special equipment A-8275-B and B-8275-B inlets.
This third pic shows the cast-in part numbers of the different water inlets.