I think some of them are a bit toooo extreme, one offs..... maybe they should be kept that way.
You wanna do something that sorta keeps the shape of the car, like below (these are my older pics)
http://www.cliosport.net/gallery/clio16v/jasontuvey1.jpghttp://www.cliosport.net/gallery/clio16v/s-jasontuvey1.jpg
http://www.cliosport.net/gallery/clio16v/jasontuvey3.jpghttp://www.cliosport.net/gallery/clio16v/s-jasontuvey3.jpg