*all images may include upgraded options* 20’4″x66″ sled starting at $29,995.00! including 115 evinrude e-tec pump and tille. our 20′ 4″ flat bottom sled is. This classic style flat bottom 14 foot jon boat is versatile and it’s easy to build. get plans and kits to build your first amateur boat at bateau.. Specmar aluminum catamaran hulls are either symmetrical or asymmetrical in design. a symmetrical hull consists of two basic v-bottom hull structures..