In that case have a blast wherever! The other 95% of the park is traversable stock to slightly modified. We stayed at Uwharrie cabins recently, which were awesome and very close to the park. As for camping, there seem to be very few guidelines at all. We did a couple "night runs" on some of the smoother trails and saw tents tossed up wherever people stopped at the end of the day. For the aforementioned reason though, I'd avoid pitching camp too close to the trails; maybe look for a flat spot 20 - 50 feet back from the main line.
-Have straps available in each vehicle in the group, and tow points front and rear. A winch in the group wouldn't hurt.
-Plan for food an water. You can pick up all the supplies you need at the big trading post by the trail head, just have a means to carry/cool/heat enough for your stay.
-Flashlights and/or aux lights on the Jeeps are a must for night wheeling or camping.
-Bring a saw/hatchet for firewood if you aren't using a camp stove, and be smart about the fires. Dig a pit for it and bury it when you are done. Don't go cutting down trees for the wood. Find dead stuff on the ground or bring in a bundle of logs.
Be prepared for a ridiculous amount of dust on the main access roads. It gets EVERYWHERE if you run topless/doorless.