This unit incorporated a propshaft rear half enclosed by a torque tube. One of the others did not, and was described as leaping about on takeoff.
The changes made from prototype to construction can be seenclearly here - running boards added, a higher windscreen, different radiator shell, more refined mud guards.
The 1923 model still featured the scalloped scuttle and square shaped doors. The 71 or so pre production cars had the prototype's radiator.
