Probably 8. Griz should beat Sac, Weber and South Dakota and be in no problem. It would take an epic collapse to not make the playoffs.
edit: It used to be 7 D-I wins. Now they count strength of schedule. In the Griz case the D-II win did not help with SOS. Based on that I would say Griz need 7 D-I wins still, which means 8 wins overall.