T2's building is naturally tall anyways. If there's any easy way to build, it's up.
What I'm fascinated by is which way they'll splice the auditorium. Cutting down the middle seems likely, but exit and access will be tricky. Size is no problem, seeing photos online, the main theater at USF is freaking tiny! (apparently the building is much smaller than our T2 footprint as well) No wonder they have such gigantic lines for this ride, capacity must be a bitch.