[twindman]

Also, if you really want to see the sights go to Yellowstone and then east thru Cody to Buffalo. I hear Yellowstone is much less crowded after Labor Day. (and if you do this, do not take 14 Alt over the Big horns. The Mountainous driving books call this the 'Oh My God' hill. 8 miles of 8% grade and 10 miles of 10% grade.
14 is pretty good (Shell Canyon) with a rest stop/visitor center part way up. Or if you like getting away from it all (boondocking), take US 16 over the mountains and stop at Sitting Bull NF campground (book early). It is at around 8500 elevation, in the forest, with a nice meadow sometimes populated by sheep and herders - no hookups tho.