Are there still observation "points" along the stairwells on the corner of the tower? Years ago,before I "discovered" the rooftop, this is where I watched MK fireworks (maybe the 9-10th floor). It occurs to me I haven't actually been out to one of these stairwells probably since the 80's, despite numerous Contemporary trips, so it's possible things have changed (the remodeling a few years back, perhaps) or been blocked. This provides a remarkably poor substitute for the roof, but you might at least get higher than the 4th floor. Not sure how high you can go regarding the concierge floors, though.