I've featured the Ford GT40 previously and here are three photographs of cars in Gulf livery taken at the Coys International Historic Festival meetings at Silverstone in 1994, 1998 and 1999.
This is Martin Colvill's car which took part in the Motor Sport Pre-'70 Le Mans Car Race at the 1994 meeting, sharing the driving with John Fitzpatrick. Car number 89 alongside is the Ford GT40 of Bobby Bell.
The 1998 meeting celebrated 50 years of racing at Silverstone and there was a special display featuring a car for each of those 50 years. This is the car representing 1969 and the programme of the event says that it's the Ford GT40 of Martin Colvill, although it doesn't seem to be the same car he raced in 1994. It's not listed in the programme as taking part in any of the races at this meeting.
In 1999 Martin Colvill entered this car in the Coys of Kensington 80th Anniversary Trophy for Pre-1972 Le Mans Cars race, and it seems to be the same car I'd photographed the previous year. The programme has it listed as 'Ford GT40 P1084', the '1084' presumably being the serial number of the car as detailed here.