Here's some more information on CANAMEX:
It even talks about a designated "Interstate 11" for the US 93 stretch from Phoenix to Las Vegas including the Hoover Dam bypass, and then extended to Reno and Boise.
And here's the official CANAMEX website:
site list a High Priority Corridor 43: U.S. 95 in Idaho, which is described as the North-South backbone of the state of Idaho:
Here are all the U.S. Congress approved High Priority Corridors (well at least what they were in 2000):