[rotorwrench]

The bushing type armature is used with the bushing type rear support cover. The armature has a larger diameter and a longer dimension at the bushing end. It has the short taper at front.

The bearing type armature is stepped on the rear bearing end to fit the bearing and is shorter in dimension on the rear bearing end. It has the long taper at front. The bearing rear support will only work with the appropriate armature.

Some early tube type housings have the terminal closer to the front support cover. The later tube types have the terminal closer to the rear access cover toward the rear of the housing.

I've never tried mixing and matching housings, armatures, and supports. With the different armature dimensions, it would be doubtful that they interchange. The bearing type tube generator with the longer taper at front was the first type used in late 1928 but it was a fairly long draw down since both the 3-brush Powerhouse and the early tube type were both in production during that time. The assembly plants just used what ever they were supplied with during the slow transition. Henry was always worried about labor strikes with his suppliers so he used as many different suppliers as he could to hedge his risk factors in that respect. They were building a million cars per year so there was always a risk of shut down.