Been sorting out transmission bits in the spare parts department. Found this "transmission driving plate assembly' in the pile. Does not look like any of the others I have. It is compatible with the narrow brake drum models, pictured is a 26 bake drum with the original beside it and this one on top.. doesn't go in the drum. I think Henry just liked riddles. The 26/27 carries the Number T 730 B, The pre '26 one is Numbered T 730, and this odd bod is T 730 F. It also has a hole in the centre shaft flange beside the rivets not present in the others. Any idea what/when/where?
Very early one I would say, as it has a key way for the clutch trans shift.
I agree with Frank. Early as it forms part of the brake drum surface and even earlier again with that anti rotational key for the clutch sleeve