We recently returned from a similar trip a few weeks ago from Jacksonville,Florida. Our rig is 60ft. w/ the toad trailer.
We visited Badlands, Yellowstone, Grand Tetons, Bryce Canyon, Zion, Capitol Reef, Grand Staircase, Arches, Mesa Verde, Pikes Peak, Rocky Mountains, St. Louis Arch, Mammoth Cave and a few other places I can't remember at the moment.
At Zion, if you want to go through the tunnel (which you do) the length limit is 53 ft, so you will have to unhook the toad. At Pikes Peak Railway station, the parking will not accomodate you. They looked at me, laughed, and turned me around. We just parked on the main drag and used the Jeep. In St. Louis there are low bridges at the waterfront (12ft) that you will want to avoid. Those are the only size issues we encountered on the entire trip. As for the roads, no problems at all. Well... the DW's butt did pucker a few times on the hairpins, but I thought they were great fun!
Have a great time and tell us all about it when you return.
'97 Fleetwood Discovery 36RS
'01 Road Star Midnight Star Edition '77 CJ-7 factory V8
'69 1600 VW Sand Rail '09 EZGO RXV Custom Golf Cart