I have an 86 Rhodes with the OLD motor mount system. Manual operation with the pulley system. I have replaced the old tracks with aluminum tracks replicated by a local machine shop.
Still the motor fits on the original Starboard material. I currently have a 8 HP Yamaha with power thrust , electric start and electric/hydraulic tilt which weighs in at approximately 100 lbs. My existing motor has the standard sailboat 20 in shaft.  I am thinking about a replacement. I want to stick with Yamaha because of the shift control located forward on the handle. I have been looking at the 9.9 HP , which comes with a 20 in shaft as well as a 25 inch shaft. My main concern is will the 25 inch shaft interfere with the rudder? I have seen a 25 in shaft on Lee's S/V At Ease, but he has the newer system with the electric rail system to raise and lower his motor. SO. . . Does anyone have experience with a 25 inch shaft motor on the OLD SYSTEM. Would the 25 inch shaft allow me  NOT to have to lower the motor as low  and allow me to have more access to the controls. ( my theory)  But I will take experience over theory in making a decision.

Thanks as always for the information, you guys are great. I know I can always count on Da List for knowledge and decades of experience.

Cary
S/V Whisper '86
Claytor Lake , VA