Steps to create the perimeter boards for the floor.
Note: It going work out better if you do not drill the corner bracket holes until you have the metal corner brackets attached to Backboard.
Start with a board 1.5" thick 43 inch long and 8 3/4 wide.
Cut/drill all 90 deg features.
Cut Pan board 3 3/4 slot in the center of the board at 90 deg.
Cut 1 1/2 rabbit slot 90 deg at rear of board
Cut 1 1/2 notch for door post 90 deg
Drill two 5/16 holes for bolting to C channel 90 deg
Cut 10 deg angle from front to back. Note: 10 deg is 2 1/8 rise over 12" (4 7/32"/24")
Cut 4 deg angle from front of pan board slot to back. Note: 4 deg is 27/32 rise over 12" (1 11/16"/24")
Cut corner profile from back.
Complete these cuts for both the Driver and Passenger sides
Attach the metal corner brackets to the Backboard using the holes defined in the Backboard drawing.
Place the Backboard onto both of the Sideboards and square up. Note: There should be exactly 30 inches between the front section of the sideboards (the metal pan fits here) and these boards should be absolutely parallel.
Once the sideboards are lined up, mark and drill the holes down to the sideboard. These bolts were originally carriage bolts with the nuts on top what size and were they countersunk?