Ready to build the walls on my Hilander

I used birch 3/4" plywood. The Scotty originally had 1/2" ply, so I had to rout out the area that attaches to the floor deck sides to make it 1/2" with the remainder sitting on top of the floor (if that makes since). So, the attached picture shows the black area is the routed out area that attaches to the side of the floor deck. To attach the plywood together, I routed the edges to receive a spline (think tongue and groove). I then used three 1" x 2" the full length of the walls to keep them all together.

The Scotty's use the cabinets to hold up the walls. I found it easier to build the floor deck (with 3/4" tongue and groove plywood), then tile the floor, then place the cabinets, then add the walls....with the help of 2 other people. The walls screw into the floor deck sides and cabinet. With the routed out area, it gave a small ledge to sit on top of the floor so we knew everything was in place. Not sure that is the correct way, but that's how I did it.