Paul.....First off, thanks for all your help. I built the seats from scrap 1/4 inch mahogany ply with 1x2 cedar inside for strength trimmed with mahogany. They are light weight and absolutely rigid. I put a cap over the exposed plywood sides on the gunwales and reinforced the transom for a small motor. The non-skid on the floor is silica sand in varnish on the inside deck. It's effective and clear enough it almost can't be seen. I chose a satin for the final finish coat. In the pic I don't have the oarlocks installed but it looks great and the part I hadn't anticipated is the number of people who come to talk to me when they see it on the trailer.
Ken