what's the big deal about putting it on the front? it's a lumina buddy, they're not meant to be sexy, flashy cars. and trying to tell the cop that "oh it was there before" wont fly cuz there's a good chance that he's not an idiot and will realize there are no holes in your bumper.
i say just put the license plate on there, most cops won't care if you really were or are just faking ignorance to the law. the law is the law and it is your responsibility as a driver to be aware of the laws that govern you.