aerohead -
Here is a normal 1980's Trans-Am with a spoiler that appears to closely match your template :
Now, if we were to turn the Trans-Am into a "Limo Trans-Am", I would like to know how to apply the template. Assuming I elongate the Trans-Am from the point of max camber, would I (B) keep it in the same place? :
Or (C) be allowed to slide it to meet the spoiler? :
CarloSW2