The prototype at first assembly.
Following the advice, found around the net, of the Model A trucks (named AA) and model B trucks (named BB) rear bell housing/ clutch housing being aprox. 2" shorter, than the normal A or B, I aquired one of each some years back - it was these housings,
that lid my fire of the idea of getting a M40 in an A.
I have read about different ways to mount the M40 gearbox, but in my mind (and on my drawing board), the idea about mounting it like it is on a Volvo - by threaded holes in the clutch housing -
When the tool for placing the holes were done, I had my AA drilled and threaded to match the bolt pattern of the M40. Afterwards testing will show, if the cast iron of the housing can withstand the torque transmitted to the gearbox.