Mason Dixon ran index class way back in 69. They must have had 30 indexes. AA thru Z. You would pick your class, then run heads up with everyone in that index. Might have 20 cars might have 1 car. After they ran all the index classes, they would then run all the index winners against each other. That was bracket style, except your dial in was the index number, not your hand picked choice. It was a lot of fun the way they ran it. Still seams more fun than todays bracket racing, course everything still seams more fun back in the 60's