Hello -- I recently purchased a 1928 5'8" Chickering Ampico A and
I am gradually unraveling this puzzle before I get ready to rebuild.

Going through the 1923 Inspectors Reference Manual as well as the
"How to Rebuild An Ampico Model A" from the Vestal press, and based
on what I see in diagrams, I am missing the automatic expression cutout
block and the two equalizer pneumatics that are held open by springs.
It looks like my instrument may also have also had loud pedal
compensators, which are missing too.

Are there any sources such as Ampico "junkyards" for parts like these?
Any help would be greatly appreciated!

John Kiszla