Why not this..?
http://www.vitesse-motorsports.com/t...016+camaro.htm
Worked great in the 5th gen. Haven't seen one yet in the 6th but I was impressed with it previously.
Also, not related to the controller above, doesn't the track mode setting have a slightly less sensitive throttle than the sport mode? I remember reading that somewhere for the ZL1. Not sure if it's the same for the SS as well.