Floor and transom

[Bushwacker]

The inner liner adds a significant amount of torsional stiffness to the hull, so i would be very cautious about removing it. If you'll notice on the 20' CC models, there are no openings in the side of the inner liner in the aft section of the hull and I believe that's because it significantly stiffens the hull. Knowledgeable guys who have removed the inner liner have compensated by installing 1/2" balsa core covered by a layer of fiberglass to the inside of the hull sides. Regarding sagging, the SeaCraft fiberglass stringer system is very stiff because the cockpit sole is bonded to the top of the stringers, basically creating an I-beam structure. The only sagging I've heard about is that when guys remove the top cap, if they don't install some cross beams, the hull sides will tend to bow outward if there is nothing to support them.