RE: Flex shaft instead of prop shaft?
I notice the drive comes right out the transom on that boat whitch will make any strut adjustment impossible , you will need to angle engine and run the flex shaft tube thru the bottom of the hull,what you are doing is kinda reinventing the wheel on this boat but anything is possible I guess. The reason they put that sort of drive on the hull is manufactuing cost is much less than the way it should have been done,, they knew the ujoint would not hold up when they designed it.