Yeah, that might be possible, though it would definite require some major wing redesign, too, to properly anchor those floats to structure (not impossible, but challenging). The other approach would be to rewing the aircraft with new wings and engine installations more like the V280's where only the prop-rotors and immediate transmissions rotate; that would get your exhausts out of the water. In that case, you might want to widen the main landing gear sponsons to provide better stability in the water.