I had a 1980 20hp Mercury that had the tiller handle removed to put on the boat that was a stick stear. The whole setup was homemade and ran off of a cable steer setup that was ran through pulleys in the back and just attached to the front handle of the motor to make it turn. Is it possible the motor was setup that way before you got it? I sold the boat and unfortunately don't have any pictures of the setup.
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