Sinista's R32 GTR is quite modified, and crossed over DIckson motor registry no problems. If the modifications carried out are legal, and done right, you should have no problems. But since you say it is stock, there should be even less of a problem. If it's a 1989 model remember you need to carry out the required changed to make the car legal by Australian standards, including Side intrusion bars, fuel filler restriction, child restraint points, high level brake light, etc.
Good luck