Here is the Reds and Cardinals schedules by opponents record with regards to .500. The first number is counting the each other's +500 records and the number in parantheses is with each others records not figured in. If the Reds/Cards play a team more than once in a month I doubled the figures to try and keep things equitable.
Cards Reds
Opp. Opp.
April +24 (+17) -12 (-24)
May -23 (-23) -33 (-33) The two don't play
June -30 (-37) +27 (+15)
July -49 (-49) +6 (+6) The two don't play
Aug +4 (-11) +9 (-15)
Sept -2 (-9) -24 (-36)