I had started to build an aero cap for my old Ranger (the '97) and had worked out all the angles pretty well. IIRC it was about 3-4 degrees at the edge of the cab to most closely fit the template. Then up to about 7 degrees and then 12 degrees to the tailgate.
This old thread has some of the pics. Never got a chance to finish it and now the Little Black Ranger it gone.
http://ecomodder.com/forum/showthrea...e-20945-5.html