Where is the base kee klamp located on the 2 x 8? Is it centered or is it aligned with the edge facing the playing field? The pictures show the rail on the edge of the 2 x 8 but the drwing show the rail centered.
The keyclamp bases are centered on the 2x6 (edited by Martus), The photos are the actual parts that will be used for the field. Be careful and be sure of what you think you are looking at, camera angles can be deceiving.
2x8?
I thought it was a 2x6 sleeper around the railing.
The size is of the bottom board 2 X 6 standard lumber. Actual measurement is 5.25 or so depending on shrinkage.