Well if you go From Bryce to Zion, you should be OK. Take the most direct route, US-89 south to west on State Highway 9. There is a long tunnel on that road. They stop traffic on both sides, charge you $10 per coach, and tell you to stay on the center line. Height is, I think, 13'-6" but not real sure about that. I know we measured the 3-rigs we traveled with(all motorhomes), and had to remove a CB antenna as it would have been to tall. Other than that it was no problem. The tunnel is interesting and is not straight. It even has windows along the way (that was so they had a place to throw the rock out). After the tunnel you will enter an area of lots of switch backs, but you will be going downhill (about 3,000 feet).
