Hi
Can you put a 4X4 gearbox on a 2wd and just leave the car on 2wd?

 

in a word no!

 

if am not mistaken the gearbox tunnel will need cutting and welding to allow space for the transfer box to fit, but if that were done in your case bud the transfer output to the front diff would just spin away. the torque wants to find its easiest route so with no front drive shaft to a diff the gear box will power the front end, i think lol. Thus No power to the RS end.