there was no uk nismo cars ever made...
what you did get was a factory fit, like mines. basically all the parts were ordered and put on before delivery from the factory.
it took 3 months for my car to come from being ordered(according to nissan) as the guy spec'd it with as much nismo stuff he could buy... (before anyone comments, it did also have the nismo zorst, but got sold)
even some of the aftermarket genuine nismo kits dont fit perfect, the biggest thing i noticed was with the spoiler, the fins at the side which come down to meet the bootlid should be tight fitting, mines are really tight with no gap, where as alot of them i have seen, even though genuine, have gaps.