Since you have the late model 350z the 370z vlsd from a manual should drop right in if I understand your question correctly. You only need to change when going backwards i.e using the quaife diff made for early model 350z you must change the stub axle to allow for fitment in late model VQHR motors (350z or 370z).
Thanks,
Alex Goodwin
AlexG@motionlabtuning.com