Wow, thanks guys for the quick replies. I had received info from the Managing Director, Peter Bailey, on their kit and differences between the GT40 and the GT1. They share the same chassis and suspension, but the GT1 is for racing with 18" wheels, bigger brakes, rear wing and wider body. It is not a monocoque like the RCR that Fran makes. I will see if I can find out more details from Larry.
Cheers