My brother-in-law sent this Reddit thread to me and I thought it was interesting.
Basically, you can flip any win or loss on the schedule, as long as your end up with the same record at the end.
So basically, for every loss that you change to a win, you have to change a win to a loss.
I think my pick would be swapping Penn State with Purdue. Ohio State would still have won the Big Ten, but would have one road loss against a ranked team.