I have no experience in lighting a tank that big, but it's dimensions and the type of corals you want to keep will be a factor, oh, and budget. I have 2 Radions over a 34X36 "cube" tank, which is on its way to being sps dominant.
Well you are going to get all kinds of stuff on this question. LOL. Just for reference.... I have 4 GHL Mitras pendants over my 255gallon which is 6ft long 27" depth and 29" high and its heavy populated with SPS.
That being said. It depends on what you plan to do with your aquarium. Is it going to be a reef or FOWLR. If its a FOWLR you can get out pretty cheap. If you want a reef say sps dominant or mixed than you will want high PAR lighting. If you like say just mushrooms and leathers, then you can get away with a little cheaper lighting setup.