Here's a link to a 2009 paper by some GM guys looking into CAE,CFD,Morphing,etc..
On one page they show an color,image-nested aeroback car with 5-different rooflines and 5-different drags.
One roofline provides a delta-Cd 0.011 reduction.
I was able to color print this single page.
http://www.beta-cae.com/events/c3pdf...-peddiraju.pdf