1ST TIP - lose the carb program only because you're going to need something to run the coils and transmission anyway, why not have it run the injectors as well? Running a carb with a 4L80 on an LS will require utilization of every electronic part on the engine except the cam sensor and injectors. If you want to run the Eddy intake, then get the one that takes injectors and rails and put a Holley or equivalent TB on it.
450 HP from 6.0 is a mild cam, 210-220 duration at .050". BTR's Truck Norris will handle that with it's eye's closed. The Comp recommended above will work, a SS2, the Sloppy 'Best' cam as well. There are many cam options.
I should've started by asking how are you planning to run the coils and transmission?