Here is what I did tonight on this project:
I took off the cap/ spoiler (four nuts and four screws). These bolt holes will make a nice mount point!
I also made a cardboard Kammback:
I followed the roof line strait back for 26" (out from car) that part is also 38" wide. for the sides I wend down following the car's side curve. Out 8" at bottom, 21" on the long side inside bottom to back top.
The cardboard sags a little to low (is not exactly following the line of the roof). other than that comments?
How do the angles look? will this help or hurt my cod?
I need to find some used election signs to get some free chloroplast to make the real one, but this helps me get the idea in my head.