It has been long enough now (since circa 2000, Yikes) since I've driven the Alcan that I'd want to get the Milepost for the maps and general layout.
However, even back in the 80's and 90's when I was driving the Alcan frequently enough that I had my routes (primarily Los Anchorage - Montana or Idaho) almost memorized, I would do as Sue did and get the milepost on a regular basis just because it was a good resource.
I always felt that having the Milepost kicking around the back seat was a necessary element of driving to/from Alaska. Even had one stuck in the back seat of the plane the couple of times that I made the flying trip.
