Silverstone - Copse Corner

[McKay]

Hello,
I was watching today the 1992 BTCC Review and I had watched the 1988 Review not so long before. I noticed a change at Copse corner. This change was that the was a green piece of tarmac by the entrance and that there were outside kerbs through the corner and a partial apshalt run off. Now I thought this was strange as to my knowledge, Copse didnt change until 1994, when it got tightened alot to slow down the cars. Did Copse change slightly in 1991 when most of the circuit changed? And when copse was opened out again in 1997 did it revery back to the original corner, the 1991 corner or something different. Any help would be apreciated as I am making Silverstone for a game and want it to be as precise as possible.