When heading back from the Missoula rally, someone told me that Rt 2, while not an interstate is heavily travelled by trucks and was not all that much fun. Instead he suggested I take Rt 200. This secondary highway meanders across Montana, ND and MN to Duluth. It was a wonderful suggestion. The road was virtually empty, in good shape and passed some nice scenery. There is one stretch where they warn you about no gas for the next 180 miles or so and mean it - I got the next town on a Sunday evening on fumes, but did make it.
(Want to work in Communications at the rally? :-)