NFL Films: More Than A Game (1970)
This you-tube video starts with the Vikings which is why I put it in this thread. For Bud Grants first 3 years his QB was one Joe Kapp - as unconventional of a NFL QB as you could envision. In his first year they called the Viking Stadium "Grants Tomb" because they lost so much - see about the 6:45 mark in the film. And yes there was a day when the Vikings played outdoors. But Kapp would get them to the SB in year 3 and lose to the Chiefs - the first of 4 SB losses.
Following that there is a piece on Dick Butkus, Lou Saban as HC of the Broncos, and Willie Davis's last game with the Packers. I forgot about the fan thing that starts the video. Just get past that to the Viking segment.