Joe, I'm sure Mark will jump in and correct me if I get it wrong so here goes, Greg and Mark were running 1 and 2 in the rookie race. They went down the backstretch I believe on the last lap and got to turn 3 and Emil was a lapper. Mark went low and Greg went high to get around Emil and they had the meeting of the minds on the other side of him. It ended up with both of them and maybe even Emil flipping. Greg ended up outside the track and the others stayed in the ball park. This is a photo Jack took that ended up as the centerfold of Stock Car Magazine. All the drivers made it back the next race which was the rookie championship race.
Disclaimer- Being that this was almost 38 yrs ago my mind may be a little foggy.