I recently bought a 1925 Mason and Hamlin 5'8" Ampico A grand piano.
The plate says AR 33089 which is the model and serial number.  The
Mason shipping information says that it is a model CAR.

I have been told that, according to shipping records, this is one of
the first Mason Ampicos shipped after American bought out Mason and
Hamlin.  The C on the shipping records indicate that the piano was
modified to accept the player.  You can see where the beams were moved
in the factory, but did they also alter the tension device underneath?

Randy Hammond