I assume your going to cross in to Canada and Alberta at Coutt / Sweetgrass.
From there follow the hwy up to Lethbridge and then on to Fort MacLeod. From here you follow Hwy 3 west towards British Columbia it's about ( if I remember) about 40 miles to the Hwy Jct with hwy 3 and 22.
Follow Hwy 22 North all the way to Hwy 1.
There is a nice campground that we stay at when we visit the kids in Cochrane called Bow Riversedge campground, which is about 10 to 12 miles past the Jct with Hwy 22 and Hwy 1, in Cochrane.
Take Hwy 1 west to Banff Lake Louise and then take at Lake Louise take Hwy 93 North to Jasper.
Once past Jasper take hwy 16 towards Hinton , just before Hinton there is another road which is Hwy 40 . That road will take you right up to Grande Prairie. About Hwlf way up Hwy40 there is a town called Grade Cashe, fuel stop and it does have a nice community camp ground the last time we went through.
From Grande Prairie it is a short drive over to Daswon Creek.
My DW is From Stewart BC and a few years back we did this exact route starting at the Jct with Hwy 3 and 22, North up to Watson Lake and then down Hwy 37 to Stewart / Hyder Alaska.
I'm pulling a 34' 5er so I feel your pain on city driving.
Soup.
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