During the World Contest of 1970 -- held in his home waters of Victoria -- Wayne Lynch rode a stubby hull that was under 6 feet long. Being so short, it was far from ideal for the old school, '6-man-heat' style competition, where hustling for waves was paramount.
A collection of 8mm home movies of the early stages of the event is lurking on YouTube. The surf is complete garbage, and the surfing is painful to watch. (It was so bad, they threw out the results of those heats, and started over again.)
Regardless, buried in the footage is a quick glimpse of the bottom of Lynch's hull as it washes over the rocks. We can learn a bit about his board from those images...
-- It had no tail lift. Like Greenough's spoon kneeboard, the back half of the board was dead straight.
-- It had no V. The tail was flat.
-- There was no edge in the back. The rails were dropped, but soft.
-- The flex fin was tall, with a narrow base. It reflected thinking that was so advanced, it's still valid today, 47 years later.
-- The fin was set maybe 8 inches up from the tail, which was/is a conservative placement for a hull. It was very much a fin-driven board, meant to be surfed off the tail.
This may have been the last displacement hull Lynch ever rode. Rolf Aurness and Reno Abellira, both influential luminaries, were riding first-gen down railers in that contest...a path which Lynch and the rest of the world would soon follow.