I had a similar assembly on my Harding and I made special encoder shafts.
Could you make a plate that mounts right on the end of the motor case to
put the encoder on? then use the cover over the encoder

Karl



The encoders I told you about look like a tight fit. Sketch it up before
your order. USdigital does make smaller encoders that use a 1" wheel, or you
could try the digikey ones Jon Elson likes.

Karl