What is the best way to install knee braces on a Shearwater 17. Fitting out CLC kit. Taking kayak lessons. The instructor thinks foam knee braces need some sort of rigid support on inner edge to keep knees from sliding off toward center of boat when learning to roll. He may never have seen a Shearwater. He just doesn't like the fit of other CLC boats he has seen. I have seen a CLC demo boat rolled and I think it was just padded with flat uncontoured foam.