simplest would be to drill a couple of holes in the bumper and bolt the plate to it. Tacky? Yes, so I would instead go to a wrecking yard and try to snag one off of a Dodge and bolt that on.
My 2008 George town 350 SE came with out a license plate, I don't want to drill in the fiber glass bumper. For me I covered tag with clear plastic and simply put in in front windshield and put a stuffed pillow to hold tag up. Works for me.