As a very quick sanity check

14 x 6 = 84 square feet

if submerged 3 inches (1/4 foot) then you have

84 /4 cubic feet = 21

21 x 64 = 1344 pounds flotation.

Since in a flat square cross section each inch of submersion will
require the same weight two inches submerged = 896 lbs approx.

There is still the issue of weight distribution on the boat that could
mean a significant depth at the stern since the outboard is actually
outside the boat perimeter.

If the front edge of the boats bottom is at the water surface because
of weight towards the stern the depth at the stern will be about 4
inches.