We had several places with computer rooms (back in the olden days when we had a lot of 3p load) and class A office space on 240 center delta. It is not that hard to deal with. The single phase 120/240 panels, out where the civilians work, look the same and you have a 3 phase panel up stream. You get a fat single phase pig centertapped and a smaller single for the wild leg.
(something like 25kva and 37 or 50 on the 120/240 side)
As long as your 240v loads are 3p there is no issue at all. The only time you get in trouble is if you don't balance single phase l/l loads on the 3p panel.
