Thank you all who responded to my question on quieting a piano in an
acoustically live room.  I'm going to try foam in-between the uprights,
since dampening the sound board a bit makes sense.  The felt between
hammer and strings seems would be difficult since I already have a
mandolin attachment (which has felt in the bass section).  I'm afraid
this might quiet the treble section a bit too much.  I'll post my
results.

Michael Concordia