Was lucky enough to see Grp B's in action several times. I have watched F1, Le Mans 24hrs (Bikes and cars) World SuperBikes, IOM TT, BTCC, German Touring cars, Irish Road races (NW 200, Tandragee 100) and the GRP B was the best.
It had action, danger, suspense...........High Octane thrills a plenty, often just a few feet away. Something about a Welsh Forest at 2am, waiting for Vartenan, Rorhl, Mouton
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etc. Pity it didn't last.
I remember the Henri Toivonen accident, I also remember Tony Pond Crashing his Rover Vistesse in Knowsley Safari Park (on the 1st Stage of the RAC 1984. Perks of living near Chester. Also met Murray Walker driving a new Rover 216..........