Another important measurement that should be considered is the distance
between the hammers at rest on the rail and the strings, also called
the hammer blow distance.  As I recall, the recommended distance for
the modern full-sized model K52 Steinway upright is 1.75 inches.

I don't know what Steinway specified for their 1917 model, but it is
probably in that ballpark.  If the hammers have flattened out or been
filed, then shimming up the hammer rail may be required to restore
aftertouch -- which will mean raising the capstans and possibly
adjusting the damper spoons again as well.

I've wondered why the Aeolian Company didn't redesign their upright
stack at some point to make regulation to the piano easier.

One more thing, for anybody like myself who uses those 'supply house'
keydip blocks.  There can be quite a variation in these blocks,
depending on the supplier and maybe what day of the week they're
running the saw.  I would double-check that the block thickness
actually matches the number printed on the bottom.

Richard Friedman