Yeah, 89 GTRs dont have side intrusion bars, they def need to be fitted.
There's been plenty of rule changes since Oct03, most notably you now require an engineer/RAWS to sign off on roadworthiness and compliance mods. Also, the areas that need mods are different from model to model, so mods needed for a GTR may be different than a Silvia, 300zx, RX7 etc and vice versa.
Thanks for the input guys, all opinions/experiences are good to hear!
Mat