Welcome to the RVForum, Amy.
I too pulled horses however, with a 3500 Chevy 1 ton long bed. It was a dually. I also had a camper on it. It was longer than the 8' bed; but I had a special hitch made because I also pulled about 8,000 lbs of horses, tack and feed. You do not need to remove the bumper at all. It will not interfere with pulling the trailer or interfere with getting into/out of the camper. I don't mean to offend you; but you do realize you do not use the bumper hole in the bumper to hook up the hitch; but instead use the underneath hitch that is screwed onto the frame of the truck. I mention this because I have run across folks who thought they could just use the existing hole in the bumper to pull a large load. If you are having a hitch put on, be sure you use a hitch rated for at 10,000 lbs and use equalizer bars.
Have fun, I spent many many years horse camping with friends and even went to horse shows.
Marsha~
