Also...a blast from the past...gospel according to Arlie:
PASS COVERAGE ASSIGNMENTS...4-3 DEFENSE
2WR 3WR 4WR
PC- SE SE SE
SC- FL FL FL
FS- x WR3 WR3
SS- TE TE WR4
MLB- RB RB RB
NICKEL DEFENSE
2WR 3WR 4WR
PC- SE SE SE
SC- FL FL FL
FS- x x WR4
SS- x TE x
5- TE WR3 WR3
MLB- RB RB RB
DIME DEFENSE
2WR 3WR 4WR
PC- SE SE SE
SC- FL FL FL
FS- x x x
SS- x x x
5- TE WR3 WR3
10- RB TE WR4
Back in the day when all called my own games...I would actually "fill" in the blanks with my team's attributes on the left and then pencil in my opponents abilities by receiver. When the opponents offensive set was "called"... this handy-dandy little pregame matrix would be consulted as part of my defensive play calling routine.