Here's what worked for me
I have a '95 H29.5. I use a cheapy West Marine Plastic mount mounted inboard of the seat on the top rail that runs from the seat cutout perpendicular to the walk through transom opening. I don't need to use the vertical rail portion of the mount because my motor (a Nissan 8, 15" shaft)hits the bottom rail between the motor's side plates (these run perpendicular to the shaft housing and parallel and horizontally to the water). These plates connect the shaft housing to the lower unit. I use three thicknesses of 1/2 inch line, which fits just right between the side plates, covered with a medium blue athletic sock that matches the motor color to avoid scratching the paint and to provide some shock resistance. From 50 ft away, you don't even know the sock is there. The top of the motor makes a nice armrest for the seat. I also use a stainless wire cable to connect the motor to the top rail for safety. It's also very convenient to lift off the mount and place on the dinghy by standing in the sugarscoop stern.