I was there when they added rows to to top of the east side and before the south endzone was closed. Original capacity was around 18000 and the addition brought it up to around 22000. Walked across the street from old Westgate Hall for the games. Parking was on the old ROTC drill fields and wasn't a problem. A popular chant was "All the way to Lincoln Way." We snuck in with vodka injected oranges in those days. Alcohol was strictly prohibited on campus and tailgating was yet to be invented. Fifty yard line seats behind the ISU bench were easy to get if you arrived an hour before kickoff, but there were usually 4-5000 noisy students there. Not bad for a student body of around 9000.