South end of the East would be ideal as most of the fans in that end stand at the moment. And with the East being an ex-terrace, it's just a matter of unbolting the seats and bolting in the barriers. Hell, I'm sure the club could find enough fans to volunteer to bolt the seats back in when we're in the Champions League... Pretty sure Dee had mentioned that the Aalesund Fans already do that over in Norway...
As for the away fans, bottom tier of the South with fans seated in the top tier. And again, when we're beating Barcelona, we could bolt the seats back in.