Race-tested tunnel boat and v-bottom boat plans for the amateur boatbuilder, boat racer or high-performance boating enthusiast.. Transom. plywood planking begins with an outer layer on the transom. this serves to strengthen this critical part of the boat, and to cover the ends of the stringers. Home / boat plans & kits catalog / be sure to check out these sections if you are interested in designs for outboard power. a word about racing.