Well, of course this is crazy. But with enough time on one's hands (which I don't have anyway), one could build this sixteen foot monster and roar across some upstate NY lake with some buddies... or town hop the shore of Lake Michigan. The "pan" is 3/4" ply, integral with the box member running down the middle. The box member takes the downward force of the mast... which is transferred from the mast ball by a stout aluminum tube.
These
cutaway shots show the pan, and how it relates to the crossplank, mast
support tube and front suspension. Click on the front view for a larger
image.
The front suspension is welded 1/4" plate steel, with a motorcycle monoshock taking the bumps, and keeping the steering runner on the ice. I don't show the steering linkage attached to the bell crank ball.