Phil - this link below seems to offer a copy of McLaren's most recent press release about their display at Goodwood. As far as F1s go, again they mention just the Le Mans winner being present:
http://www.racecar.com/Motorsport/Ne...wood/35467.htm
I see no reason why McLaren would keep the kind of display you (and I, and everyone) are hoping for a secret. Also if they were planning something that big surely they would have reached out to as many owners as possible so I think the fact that 16Rs new owner received no invite is another very telling sign.
>8^)
ER