Paul Lipps has used a spring connection between the flap actuator and
the elevator pushrod
to drastically reduce the trim disturbance felt when changing flap settings.
http://lancaironline.net:81/lists/lml/Message/44556.html

I copied his installation, and after a few adjustments to spring rates
and engagement
point, I have to make only small trim adjustments after lowering or
raising the flaps.
http://lancaironline.net:81/lists/lml/Message/42607.html

Previously, the full range of adjustment on the mechanical spring trim
was not quite enough
to cover the full range of operating speeds. The installation is very
simple, consisting of a
spring mounted in the center console. One end is attached to the end
of the flap actuator
piston (in a 235). The other end of the spring is attached to the
elevator pushrod.

Other messages in the thread:
http://lancaironline.net:81/lists/lml/Message/42620.html
http://lancaironline.net:81/lists/lml/Message/42654.html

-bob