I just went through this same process since I live in NY. I elected to go with center mounted bumper option, using the pre-drilled drill holes. I couldn't find a kit that was priced reasonably for this purpose so I made my own using various products on amazon for about 15 bucks and it looks great!
I also used a couple of rubber washers i had lying around so that the license plate mount wasn't sitting right on my bumper.
I used these guys here. They seem to work fine albeit a bit on the short side, still, they work for me even with a license plate cover.