That's the one of the first games I thought of when I saw this thread, along with 1970 Massillon games. I believe McK & Ignatius played each other in the regular season every year from 1994-99 and in the playoffs in 94, 96, 97 & 98. That would have covered all of those guys. McK won twice in 97 and in the playoffs in 98. Ignatius won the other 7 games.
I remember you posting about that Glenville group also. The entire Cleveland Senate league has sent a ton of guys to the NFL over the years. Same for the Akron, Cincinnati, Columbus, Dayton Toledo & Youngstown City teams going way back. If you ever look at the original NFL teams they had a lot of guys from those "City Series" teams from all of those cities. Several of those teams had multiple future NFL guys playing on the same HS team
I want to say that Akron Garfield had 4 future NFL guys, all about my age, at the same time in Jim Lash, Steve Craig, Larry Poole & Dave Brown. I think they overlapped at Garfield anyway.
When it comes to NFL players I'm not sure many people outside of Kent or Ravenna would think of Roosevelt or Ravenna but I can remember a game between the two in the 60s that had 5 or 6 future NFL players. Tom Deleone, Stan White and Mike Adamle at Roosevelt and possibly Gary Roberts but I think he was a little bit older and may not have been there at the same time as the other three. For Ravenna Don Nottingham and Mike Simone. I think it was my freshman year. I remember because Tom Campana, a Hubbard and YSU grad, was the Roosevelt HC at the time and he would get some coverage in the Vindy.
When I was a kid Youngstown South had Jay Cunningham, Jamie Rivers, Pete Richardson and Bill Lenkaitis but Cunningham was a few years older. Wilson had Rich Buzin at the same time.