Ron, I don't think this is as difficult as it seems. Using double sided carpet tape fasten two 1" x 10" x 8' boards together. Layout your shape and cut it with a bandsaw or jig saw. Sand the edge smooth. Separate and cut a rabbit 3/8" deep by 1/2" wide mirror image on the two boards. This will leave you a 1/4" wide "retaining wall" with 1/2" wide support for the plywood. Cut your 1/8" ply to width and fasten down with contact adhesive. This gives you one lane. Use the other 1 x 10 pieces you cut off; flip them over and repeat the process to get the second lane. Repeat it all for the next two lanes.
"Living in the D" (this means Detroit!)
"It's fine to disagree with other members as long as you respect their opinions"