Unless your undergraduate GPA was sorely lacking (below 3.0), I think you should just apply with those scores. Would it really matter if you got in with a 740 as opposed to getting in with a 760? Maybe scholarship money, but getting in is the bigger problem when you look at the big picture.
A 740 is still above the median at Harvard, Stanford, MIT, UPenn, Northwestern, Chicago, NYU, and Dartmouth College. Even top schools not in the US like London and INSEAD don't have GMAT averages or medians above 740.
You also risk a good chance of scoring even lower next time around too. When you average scores at a certain level in practice, I would think that you should assume that you could score a good 30-50 points below that on test day as well.