AirRabbit - in the 737, the control wheel position *should* be the only reference you need for flight crew inputs as use of the rudder in turns in a normal configuration is strongly advised against by Mr. Boeing as the Yaw Damper keeps the aircraft co-ordinated.
There is no way for flight crew to see or feel the Yaw Damper inputs, though I imagine it is recorded on the QAR and FDR somewhere.