I love that old video. Its rare to see tv coverage from the British series.
The '67 Camaro driven there by Martin Thomas is the car run in 1969/70 by Bill Shaw Racing, and driven by Roy Pierpoint.
Note further back the '70 Mustang of Martin Birrane is the car built by engineers at Kar-Kraft and used throughout Boss 302 Chassis Modification manual, created by Ford for teams wanting to build and race Sportsroof Mustangs. Chevrolet had done the same a couple years earlier.
I believe it was Don Yenko who arranged for Birrane to purchase the Mustang.