Lee,
Well, engine-mount studs that fit through the cases appear front and rear. The rear ones do not appear on the picture of the exploded motor but on the picture of the frame with the gearbox plates. The front ones go through the stamped mounts that fit around the dynamo. For those, the studs are shown on both drawings. Confusing. I still don't see where you get 14, and am anxious to know the answer, if it is not, indeed, that the extra hole you are countiing is for the breather dowel.
I am sorry, but more glad, that I don't have my cases apart to look at this first hand.
Richard L.