Five feet of tank, 8 inches of height. The BOAT52W stretches 32 gallons across a 60 x 16 inch footprint, and it exists for the installer who looked under the cockpit sole, found a long shallow trough, and wondered if anyone molded a tank for it. Ronco does, with a heavy wall, and has for decades.
It is an H.D. molding - thicker-shelled than the light-duty RV series, built for hulls that slam - in FDA-compliant polyethylene rated for drinking water, rotomolded in Tustin, California since 1974. Fittings are installed per order wherever you mark them, spin-welded or threaded. Print the drawing below and plot your fill, vent, and pickup with the on-page fitting planner; on a tank this long, where the pickup sits determines how much of the water you can actually reach.
The full-load figure is about 267 lb, distributed along the whole 60-inch run, so a continuous shelf handles it easily - just strap it against movement. See the shorter and longer planks in boat tanks, or view the complete family on the Ronco Plastics hub. OneSource Plastics is an authorized Ronco Plastics dealer.