The v-spec (324mm) discs and callipers won't fit under r32 gtr 16" wheels. 17's needed minimum, thats why nissan went to the BBS rims. Can't go callipers only as they won't sit on the stock 296mm disc, will be too far out..
I have stock 32 gtr brakes on my car, good if serviced. I bought a set of 324mm discs and dogbones and couldn't fit them under the 17" rims that I have, so even at that size you have to be careful, though with gtr offset rims you will probably have a lot better clearance.