The Historic Car Races meeting organised by the Aston Martin Owners Club at Oulton Park in September 1986 included a race labelled as Round 3 of the Historic Car Championship. One car which took part in the race was this 1958 BRM P25.
I assume it's John Harper's car, because the programme of the meeting actually shows that car number 27 in this race was John Harper's 1960 Cooper Climax, but I know that John Harper did also drive a BRM P25.
The P25 was the car with which Joakim Bonnier achieved BRM's first Grand Prix victory, in the 1959 Dutch Grand Prix.
Two photographs of the car at Lodge Corner during the race.