It shouldnt be too hard, it depends whether you're replacing it cos you,ve bumped the car? if you have bumped it then there might be a chance that the bumper backing bar is bent, that is bolted to your chassis legs and may have pulled them in, meaning a possible jig job?
But you probably know that so, i think they are bolt on, just go around the edges of the panel and take the bolts out, id stick the bolts through a bit of cardboard and write down where they came from...
I hope it goes ok for you bud