The only hitch I've seen that requires modifying the bumper is the OEM one. I believe the rest sit under the bumper.
As for tires. The stock 33's will rub in certain situations. If you want to upgrade sizes, go with 315/75R16. You will get some rubbing on the swaybar at full lock and may hit the fenderwell when flexing offroad, but its worth it.
For black on green, search for pics of Neocon1 and The Green Lantern's rigs.
