If you're expected win percentages are accurate, then yes, everything you've calculated thus far is correct.
I calculate, based on your win percentages, that the chances of Iowa winning over 7.5 games is 66.69%.
You're right, the over is the right side, based on the odds offered, if your win percentages are accurate. With the odds you're being offered, I calculate your edge to be 16.04% by betting the over on this market.