yup, that's what im doing, but in order to mount the ys I had to replace the wood rail cause the stock ones were just better than light ply. for what ever reason I put a hole in the annular ring big enough to fit the motor 5065-320 through plus a lot more. so I made a interposer to span that and epoxied in place using the spinner to locate it. when dry I put screws through. walking it out to the garage I have to rest it on its nose and the epoxy broke free and it started to chuck around.
brought it back down to the work shop to find out that the ply in the annular ring stripped out once the epoxy gave out. no problem, so I got some flat head screws and went through from the front so the wood screws are anchored in the maple.
did you have any problems with the annular ring wood giving way and the screws loosening up?
joe