Got to keep old prop, cause around here, its pretty common to have a prop strike and with a cruise prop, your not getting out of the rocks or off the sand bar. Will tell you I also have a 76/50 cut down to 74 like the book says and there is about 80 feet different in takeoff. For float go with a 80/42 or 43. With the 8040 when it unload I have to back off immediately to stop from over rpms, even in full climb. But I get 2550 at static and get off like no other citabria or scout I know of. Since I upgraded to 160hp, the 74/50 I get 2650 at static, so I have to repitch it even for backup prop.
Terry