Thanks for the compliments JC. The dimensions for the spoiler will be different for each car manufacturer since no two bodies are the same shape. What I did was tape some poster board against the rear of the car, trace the body shape with a marker, then raise the poster board two inches, and then recontour the outside edges to blend in. Took a few tries before I got the shape where I wanted it.
Once I was happy with the look and shape, I placed the poster board on 3/4" particle board. I used a jig saw to cut the shape, then sanded and sanded and sanded some more until the edges were smooth (no ripples).
I clamped a piece of .080 6061 T-6 aluminum sheet to the jig and used a router with a flush cutting bit attached. Makes a zillion hot little aluminum shavings. After removing the now cut-to-shape spoiler from the jig, I used a metal file to clean up the edges of the aluminum, followed by 150 grit sandpaper on a block to make the edges nice and smooth.
I had a machinist mill the slots. They are 3/8" by 1.5" long. I used some 5/16-18 x 1" SSTL hex drive button head screws in the adjustment slots and 1/4-20 SSTL hex drive button head screws in the middle. NOTE: The two middle screws are fixed and because of the restricted area they go in, I drilled the holes in the fiberglass undersize and use the threads of the screw to cut into the fiberglass.
Hope this helps
