This subject came up on Facebook the other day - my late father did some of the development testing and I have a picture of him in a Silver car, which was not believed until I posted it, as they were all red.
When I looked at the photo though, I realised the car my Dad is driving has slightly different bodywork, so I'm not sure if it was an early model or a later model that had some development/modifications.
There is a thread on PH too, that has some nice race pictures:-
https://www.pistonheads.com/gassing/...&t=1636547&i=0