Entering Chaco Culture National Historical Park from Highway 550

Chaco Canyon is located in northwestern New Mexico. The park can only be accessed by driving on dirt roads. From US 550, go to mile 112.5 (3 miles SE of Nageezi) and turn onto CR 7900 and CR 7950. This route is clearly signed from US 550 to the park boundary (21 miles). The route includes 8 miles of paved road (CR 7900 & CR7950) and 13 miles of rough dirt road (CR7950). The 4 1/2 miles before entering the park are very rough.

[@R.Es1]

I've read it's best to go with a vehicle with 4x4... any tips that you can give, perhaps what to carry in the vehicle in case someone gets stuck? Thank you