The rankings that are listed are the rankings at the time of the bowl game. In regards to the 1973 bowl game, they have BYU listed as the 17th ranked team. That was the AP poll on December 2nd. In the final AP poll, BYU was no longer ranked.
Since BYU did so poorly in bowl games, it is expected that their opponents would have finished the year ranked higher than how they finished in the AP poll at the end of the season.
So my numbers are still accurate, but they need to be adjusted in terms of the rankings at the end of the regular season and not at the end of the bowl games. But the rankings were correct at the time BYU played those opponents.
Sorry for the mistake.