I used 3/4 in Cherry faced plywood. I stained it with a teak gel stain. 3 coats urethane BOTH sides to minimize cupping effect. Router with a 1/4 straight flue to cut grooves every 2 3/8 inches. I ripped strips of maple on the table saw and glued them in. Carefully sanded so at to not cut past the urethane into the stain. Then 5 more coats urethane. Cut the pieces using the old shapes as a pattern. One thing that I didn't do, because I ran out of time was to coat the exposed cut edges with epoxy. I an not too worried about it because the plywood has so much resin in it anyways. I debated about using the fake teak and holly over ply but it was very expensive, and I like the thought of wood. Real teak and holly would have been nice but the cost was prohibitive. This is a happy compromise. The old flooring still looked good after sanding and oiling, but the ply beneath it was rotten and soft. It really gives the old 31 a new glow down below. It was a pretty big task, but very rewarding now that it is all down and in place. Just use caution on your cross cuts as the veneer likes to chip. Now if I can just get that boot stripe tape straight.......