[Graham]

Graham, if you did drive my C4 at the Wye Valley event, any idea where the off side wing mirror went!!!???

I am afraid I do not remember seeing it, and as the running of the Proxy cars was shared out between the attendees for different stages, it could have been lost at any time. 
As you will notice both in their or for that matter in my rules, "small details like wing mirrors can be left off the car" when entering them.

I would say that in the main that is advisable, as these items do come off and in a busy environment, even on my tracks such items go missing very easily.