To fit both caliper and disks will be very expensive as you will have to do major work to the hubs as the r32 GTR is a five stud pattern for the wheel and the R is a 4 stud. You would need 16 or 17" wheels anyway depending on the clearance. Then on top of this you will need to have a bracket fabricated to fit the calipers onto the hubs. Few years back Hi-tech or Abbey did a similar conversation cost around £1000 + fitting. Your better off trying to get hold of a set of caliper from a 200sx and then getting the bracket made up.