I have been following this thread with interest as well.  While I agree
that the original equipment should be kept with the original piano,
there are times when orphaned systems can be married with gutted
pianos.  I will relate my positive experience with such a situation.

About two years ago I purchased a 1924 Steinway Model "L" piano (at a
very good price) which had had its Duo-Art system removed at some point
in its history.  I have a fairly extensive collection of Duo-Art parts
on hand which I was planning to install in the Steinway.

About a year ago, I had the opportunity to purchase on eBay a complete
and restored Duo-Art system that had been removed from a Steinway of
about the same vintage as my piano.

To my delight the serial numbers of the two pianos were very close, and
to my surprise the entire Duo-Art system fit into my Steinway, in the
original screw holes, with little or no adjustment needed in any of the
rods and control arms.  Amazing!!

I am about three or four weeks away from reinstalling the stack, after
a complete rebuild, after which time I will have a very nice instru-
ment.

So, from my experience, it's not always a sad thing to hear of a repro-
ducing system being removed from a piano.  Sometimes there are good new
homes for the salvaged parts.

One thing to keep in mind in removing a reproducing system -- and this
should not be the preferred option -- is to be sure to very carefully
label and mark all the parts for the person who might reinstall it into
another piano.  I was fortunate that the Duo-Art I bought was carefully
removed and well labeled.

Alan Turner