Don't want to buy a new trolling motor

[dechavanne]

I have a Motorguide 67 lb 24 volt trolling motor. It has variable speed control which is called DuraAmp. The speed control does not work, so I was going to order the two electronic parts that makeup the DuraAmp circuit, which is the board assembly located in the control head, and the mossfett assembly located in the lower unit. Come to find out, these parts are no longer available. Mercury's recommendation is to convert to a digital system which consists of numerous parts for $350 plus. What I want to do is convert to a rotary switch with 5 speed adjustment. Has anyone done this before? From reviewing diagrams, I would have to remove the mossfett assembly in the lower unit, but I should be able to reuse the brush card assembly. I would have to remove the potentiometer and circuit board in the head and install the 5 position rotary switch, but I don't know if my existing handle will connect to the new switch and what type of mounting brackets I will need. Any help would be appreciated.