i have a 15 ft flat bottom back of the boat is a 20 inch. anyways a have a 6hp evinrude fisherman and the prop on the motor does not clear the bottom of the boat by about 3/4 of an inch. i have not had this in the water yet. wondering if since the prop is not all the way under the boat this would cause the boat to cavitate or if it would move at full throttle. any info would be great! thanks.