this is a factory lsd gearbox.. lsd is outside the box (inside black circle) so it needs a shorter drivers side driveshaft..
aftermarket lsd's go inside standard gearboxes so can use standard drive shafts.. if you have a short shaft off the factory lsd gearbox it wont fit into a standard gearbox.. 2 short
this is a standard box which doesnt have lsd on outside and uses normal driveshafts