A few answers for you off the top of my head
-There are no oz delivered 32 gtst's, there are 100 aussie GTRs
-U said the main differences, brakes are better but I believe the gearboxs are the same, anyone?
-Factory options are s/roof (gold), active spoiler, air purifier, different front bars and skirts, most are type-m which have better brakes and a few interior goodies, prolly a few other things.
-To tell if it has had a transplant check badges like red/blue GT on the sides, check for factory boost gauge, FAST the VIN number ask nicely and people will do it for you.
-32s do have problems with rust, check under wheel archs and under the car if it's minor it can be fixed
Good Luck