all of my cars that I have modified have been engineered. Very expensive exercise, but very worth it. My XR6T will be no different. I have already spoken to my engineer about my wheels, brakes, pedals and steering wheel (yes, the GT wheel was not a factory fit) and I have also told my insurer about my mods too. but I havent modded my motor yet, so emmisions havent changed. And I think that's the big problem here.