You do understand that the calipers used on an R32 GTR ARE NOT the same as as an R32 GTR V Spec?
These adaptor will only work with R32 GTS or 200SX Calipers; the ones that go with a 280mm x 30mm rotor. This is how you get to a 324mm rotor. These brackets are designed to work with a 324mm x 30mm 350Z Brembo rotor; the offset of the GTR Brembo 324mm x 30mm rotor is unsuitable, and also more expensive.
Applying the same dimensions (a 44mm dia increase) using an R32 GTR Caliper (which uses a 296mm x 32mm rotor) ; you end up with a 340mm rotor.
This is the last post I will make on the subject; You can argue if you like, you can even go and buy the brackets. In fact, I encourage you to do so.
You will then discover that; surprise surprise, they don't fit.
I have no problem with cheap, effective improvements, but this will not be one.