I have a Hardie -Ferodo tenth anniversary poster celebrating the running of the annual Bathurst enduro( the Hardie sponsership began in 1968 )which features a shot of each winning car (1968/1976 ) and a central group shot of each driver and they are wearing identical race suits as in the promo photo so I am guessing this was taken at the same time.This poster was made available in 1977.

Regards Pete.