I was ten years old when this went down, and I can still remember my grandfather's (a huge fan of boxing) rage.
There was nothing racial about it, and none of us, including him, knew or gave a shit about the ridiculous 'Nation of Islam'. Crazy as Scientologists, but more violent (great way to get two fatwah's, Bane).
I think I'm going to buy this book, and research it. I hope he has lots of footnotes.