Actually there were THREE!
GPMINI / GP0203 was one - see GBMINI.net for much more including my BI2007 coverage:
Ians GBMINI (MINI Cooper) ? Blog Archive » British Invasion 2007
Also GP1717 owned by George (who owns two other GPs!) - his coverage can be found here:
jcwgp.com » British Invasion Day 2 - Rain, Sun, Rain and Sun
Finally was GP0191 owned by Dave, but he didn't come on to the field - I guess the mud put him off! This is him at a different event:
The GPMINI Gallery :: GP owners :: GP0191