[incoming]

Park in Section "E" nearest the main road entering the park. That will make your exit very quick.
Carry folding chairs and coolers containing your favorite beverages and food and maybe a blanket to lay out on the ground.

Walk due north from where you parked and you'll be sitting in the trees directly over the back straightaway with direct view of a couple of turns.

Should you not bring food and beverages, you'll be very close to where the food trailers are parked.

IMO, Barbers is the best racing venue there is. I've brought hardcore racing spectators there and they've all been impressed.