KR engine numbers ( and Fred Nix )

I found these pages(here's one in particular) from AMA pro racing programs, whereas in the earlier days, racers noted their engine serial numbers upon entry for each class.  Maybe you'd find a set of cases, and could determine the racer who rode that particular machine . . . ?  Fred Nix 53KR1982: I wonder where that motor is today?  Fred was flyin' that day.

 This might be the bike?  
Fred Nix was one of the best Mile racers ever, winning mile events in only his 2nd year of pro competition - and taking victories in professional road racing nationals too.