Hello Bob,  I have enjoyed reading the information you have posted to
the MMD.  I do have another question for you, and perhaps others on the
group.

Where does the Steinway Model AR stand as to replacement of the Duo-Art
mechanism from another model?  How does one determine, possibly from
markings, from what model a Duo-Art mechanism was originally installed?

I have what I believe is a complete system, and was told it was removed
from a late 1920s or early '30s Steinway model "A" grand.  Can I verify
this by looking at the stack alone?

Let's keep this thread going until we gain all of the information
possible!

Al Pebworth
Chesapeake, Virginia