A white 1968 Camaro RS/SS 396 convertible was used as the pace car for the NASCAR events held at Atlanta International Raceway, Hampton, Georgia in August of 1968. Old movie footage shows that the Camaro was used to pace the Atlanta 250 NASCAR Grand Touring race on Saturday, August 3, 1968. It was the 12th race of the season. The Grand Touring (GT) division of NASCAR featured Camaros, Firebirds, Mustangs, Javelins, Cougars, Barracudas, etc. Donnie Allison won this race in his Mustang.
Since the Camaro was used as the pace car on Saturday, it's probable that it was also used on Sunday, August 4, 1968 to pace the Dixie 500 NASCAR Grand National. Unfortunately, I can not find any pictures or film of the Camaro during this event.
While watching my old VHS copies of Car and Track (1960's/1970's automotive/racing tv show which was re-run on Speed Channel in the late 1990's) I found footage of the Atlanta 250 GT race. I took these pictures of the Camaro while the footage was paused.