in search of scca gear info ???

i decided to look at the m3 scca car for some ideas as how to further upgrade my car, its a 420hp@8200rpm 2650lb insanely fast m. i read about the intake manifold system they use, its supposibly 6 individual butterfly valves. thats pretty sick. the rear gears are 3.87s i think. anyone know where i can find different gears, i don't see alot of companys offering them. just let me know - adam