I've had a good look over (and under) Coopers Torana. I can see why they keep the changes under wraps, as they pay a fortune to get it designed, they arn't keen to hand it over for free.
Basicly the suspension has to keep it's type (live axel, semi trailing, strut, double wishbone...etc), and then you go crazy. Most live axel rears are copies of V8 supercar rear ends, with quick roll centre adjusters, pickup points moved well forward and up, watts linkage..etc. You can imagine what they do to wishpone front ends to fix bump steer and dynamic camber.
I'd hate to think what the Porsche guys do to their semi trailing arms.
Without visiting a suspention guru, I doubt you'll find much help from other compeditors.