There are others who have taken the road more recently who can chime in, but a couple of comments:
- 287 from Texas to Montana sounds pretty good
- I was born and raised in Alaska but spent the better part of 2004 - 2016 in Ewe-stun....couldn't wait to get out and the even the drive from Houston-Dallas-Amarillo-Denver looked pretty good with some vertical relief in front of me and Ewe-stun behind me. The Rockies were a sight for sore eyes.
- 287 is a good route out of Texas, but (having driven from Seattle or Montana to Alaska more than 20 times), I have to say that I really really like going through BC as a start on the journey North......moreso than coming Northwest from Montana.
- In any case, if you can take the time, go slow through at least the Alaska Highway portions of Canada....that is almost, almost, as scenic as Alaska. Especially Kluane, Destruction Bay, etc.