I have to disagree with Coppercrazy. I blew up your picture and compared the inner curve of the 9 pointing to 3 o'clock. On the Large Date, the inner curve points to 5 o'clock. Also comparing the serif of the "S" mintmark, it matches the small date.
I have a 70s just like that there's a little nub on the curve of te nine that points straight toward the 7 also the tightness of the curve looks more of the small date variety