I think the previous year there was a race like that at Quaker City in Ohio, and a friend brought his 1969 GTX to that one.
Drove it there from So. Burlington, Vt........ raced it...... drove it back.

There was a nice video available for that event as well, along with a real good article in Muscle Car Review.
They had every entries best ET listed in the article........ there were over 200 cars iirc.
I think my buddy was mid-pack......... mid-14’s.

It was won by Bob K in his Super Bee that year......... which was in the 12’s.

He was planning on going back the next year, so I did some work on the car and had it running mid-13’s....... but he didn’t go back.