[C-unit]

I was searching through but couldn't really find anything. I am currently doing a SR swap but since I haven drop the engine in yet, I was thinking of getting a 6 speed gearbox. Car will be under heavy abuse so, I don't think the S15 gearbox will last. does anyone know how hard it will be for the 350z 6spd swap? I dont need the speedo working as it is only a track car. I will be running 430-460whp when the car is done. any input would be great.