I have a 33 GTR box in a 32 GTST.
You will need to retain the modified transfer case to make it work, it might be possible but a mission to get around.
If you cant get the GTR box in with the transfer case attatched, it would be easier/cheaper to go a 25 box.
More info: http://www.skylinesaustralia.com/forums/R3...gtr+rwd+gearbox