It's good to hear highway 37 is all paved, now. Probably some very nice curves and road condition.
I grew up in Terrace (about 100 km past the turn off to hwy 37) and just this past August went back after being away for 15 years. I forgot how beautiful the area really is. Even over a long weekend, I couldn't believe just how free of traffic volume the roads were. I suppose they're more or less the same as they've always been, but after a decade in the city, they seem pretty free of other cars.
I've never been past Stewart on that highway, so am quite interested in this little road trip. I'll certainly be paying attention to the info that starts flowing in here. Keep in mind as well, between Smithers and Whitehorse, there's about 1200 km of pretty much nothing but you and the road. And all the critters, of course...