Gavin,
I've had replies back from two fellow Cobra owners who would be willing to take a passenger for the track session. One is a very nice 289FIA with a 289 on Webers, but I don't know what the other one I'm afraid, although it is almost certainly a 289.
I think they'll both probably turn up here before too long so the can introduce themselves and make arrangements.
Looks like being a great event. I can't wait.
Paul