This is the first fitting of the center block. I decided to use a piece of 2x6 cedar for the main block. It was planed to a thickness of 1 1/8". I wanted to use something more dense for the part that the bridge would screw into so I used a piece of 3/4" 9 ply birch plywood. This photo shows just a piece of standard 3/4" plywood going part way. This was later discarded in favor of the full length piece of birch.