One would have less problems with the Z32 or R32 M spec front brakes. I used the R32 GTR brakes
Either restud your hubs or drill your rotors to 5 stud.... then
The GTR R32 are considerably taller at 296x32 , and the caliper rotor clearance is nill when bolting onto U12. I had them turned down to 290mm from 296 at the front, to give adequate rotor clearance.
I "think" the R32 mspec and Z32 would bolt on no worries. Maybe someone who's done the Mpsec or z32 swap would know.
The rear is a different story , bolts on fine but theres no handbrake input in the gtr/r32/z32 rear caliper, so you must install a drum at the rear of the u12 attesa. Im not sure if the other u12's have drums or not. I just changed the caliper to a rear MR2 caliper which fitted over the ventilated rear discs , that also had the handbrake input.