My H.C. Bay player action is in a 1928 Milner piano.  I recently had
it completely restored, but a little more needs to be done.  I've
enjoyed it since 1971.  The tracker string travels 5.25 inches.
The pole "could" travel 5.5 inches.  I did not untie it to measure.

Augie Gonzales
San Jose, Calif.