I’ve got a decent book about that fight. Titled: The Last Great Fight: The Extraordinary Tale of Two Men and How One Fight Changed Their Lives Forever
I remember my uncle walking over to my house while I was playing Nintendo and telling me that Tyson lost. I thought it was James "Bonecrusher" Smith that won and I was even more shocked when it was Buster Douglas.
I honestly think Douglas could have beaten any Champ that night. I mean any champ. If Spinks and Norton could beat Ali I don't see why Buster couldn't have. Size, fluidity, jab and willpower. It's all there. It shows you how critical mindset is. Once Buster took his foot off the gas, he turned into a 400lb diabetic mess.
Buster that night was closer to the level of your average all-time great than he was your average 'very good' like a Tim Witherspoon, Oleksandr Usyk, or Ike Ibeabuci