Under the Car FX Rear Black Out Panel, Will's crew chose an SLP Loud Mouth System to deliver an aggressive, but streetable persona. As Will said, the exhaust pipes are a bit longer on the '10. "That particular kit has enough adjustment in it that we made it work on the 2010," Russell explained. "Luckily they had enough length it actually worked." The Car FX motto is written across the rear deck of each modified Mustang.