While it is still a lot of work, I do have one trick for regulating
upright dampers which can save a lot of time:

Block the pedal so that most of the spoons start to move their
respective dampers when the hammers are 1/2 distance from the strings,
regardless of how erratic this makes the dampers appear with regard to
the strings.

Now set (by bending its wire) each damper precisely at the strings, but
with no pressure at all against the strings.  You can test this by
pushing the string away from you - if correct, the hairs of the felt
will just touch the strings, but the damper will not move when the
string is pushed.  I call this the "neutral" position.

If you do this with plenty of light and are careful, you will find
that, when the pedal is unblocked, the errors to be corrected are
fairly minor ones, and also that the work required to adjust the spoons
will not be too great.

It barely needs to be repeated that no damper regulation job can be
considered correct unless all dampers lift simultaneously from the
strings, as though made of one piece.  In player pianos, where the
automatic pedal actuators often allow only scant movement, this is
of even greater importance.

I made a special tool some years ago which grabs the upright damper
rod (it fits virtually every action) and can be rigidly clamped to the
action bracket in front with vise grips in any position, thus rendering
the "blocking" of the pedal (which sometimes is hard to do accurately)
unnecessary.  Later, the vise grips can be removed, and it can be
pressed lightly to lift the dampers repeatedly, for final testing.

Have often thought this gadget should be manufactured, it is so clever
-- but it is so simple once seen that it would be hard to charge enough
to justify making it.  It consists of a piece of 1/4" rod bent up like
a pretzel in ways I can't describe adequately in words; but those
clever enough will be able to figure out how to make one.  Everyone who
has used it has said that they can't imagine regulating upright dampers
without one.

Larry Broadmoore
Broadmoore Piano Company