Your 710 is a nice bike, but I don't think it would be a good base for what you want to do. Sell it on Craigslist (there's a pretty good market for those bikes) and put the money toward a platform that will work better for you. You'll be hard pressed to fit wide enough tires on that frame for loaded touring along the Alcan (or Cassiar, depending which way you are going), the 27" wheels are outdated (and your frame may not even accept 700c), the 5-speed rear spacing is probably 126mm and you'll need to go to at least 130mm (possibly doable) or 135mm (too much), etc.
Sora isn't bad stuff for a touring bike, IMO. I wouldn't use the DT Axis wheels for touring.