It's not difficult. Seats would need to be allocated and just give a preferred time for each section to enter at. The majority of people would manage that no bother.
Given there would be no away fans we would use the South for home fans so the East wouldn't need as many people in it.
Talking about turning up two hours before kick off is daft. If the reduced capacity of the East Stand is 1500 that means each turnstile let in 250 people which isn't a lot. If people start turning up at 2:15 you are talking 6 people a minute.