Here's Firebird during the first year it opened. Hard to tell for sure who this might be, but it is obviously a pair of mighty Mopars in this previously "never" published photo. The tail end of the Dart reflects that it is a Hemi, while the four-door in the opposite lane is either a Belvedere or Savoy (guessin'). Obviously, this is long before there were any seats on the right side of the track and sans any guardrail, too. But by all indications, the sagebrush  and sponsor signs down the track a bit were very evident in this shot.