But flying VFR over the mountains and desolate terrain in Alaska is no different than in the Lower 48.
If you were going to be doing some work in the Bush I might have different advice--but it seems to me that you're just gonna pick up an airplane and head South-east. Shouldn't be a big deal if you leave yourself plenty of time. Take food and water with you as well as a sleeping bag. Always file a flight plan. Just use your best common sense.
There are books on flying the Al-Can; you could probably do a search on the internet.
The good news is the days are getting longer so you'll have a lot of daylight and there are plenty of airstrips down the length of the highway. That's pretty much what I'd do my first time--follow the highway, that is.
If things get too dicey just set it down on the road and wait it out.
Best wishes and be sure to come back and tell us about it.
I've flown the inland routing from Nampa, Idaho to New Wasilla and back. Our route went like this: Nampa, Spokane, Penticton, Smithers, Dease Lake, Whitehorse, Haines Junction, Gulkana, New Wasilla and the same back home. This trip was in a Supercub and took a total of 50 hours roundtrip. We flew during August and the weather was really good. Canada is pretty easy to fly through. Once you clear customs the first time in Canada all that you have to do at each fuel stop is walk into the weather station and file a flightplan. Throughout British Columbia there is a regional airport about every 200 nautical miles until you get north of Dease Lake. We GPS'd between Dease Lake and Whitehorse which bypasses The Trench. Take a couple of GPS's to make your life simpler.
sounds like a fun trip. I've done the trip about 11 times. Get your charts in advance. Sporty's sells NavCanada publications. Get at least the WAC charts for your flight and a copy of the Canada Flight Supplement. THe CFS is like our Airport Facility Directories, except one book covers all of Canada. If Sporty's is sold out of current CFSs, beg borrow or steal and out of date one. even last years is better thant none at all.
There is also a strip chart for the Alaska Highway. it is based on the Sectionals along the route, but covers it in one piece of paper, instead of 2 or 3 different sectionals. I recommend flying inland rather that flying along the coast. The Wx is much better inland. Southeast Alaska and Coastal Northwestern Canada have some really lousy weather, even in the summer. Your precautionary landing options are really limited along the coast. If you're not over one of hte few airports, you've got a choice of ocean or mountainous terrain with BIG trees. Inland, you have roads (a few anyway) abandoned strips, sandbars, etc. I've done the coastal route once, in a twin, and I would advise against it in a single. Once you hit Watson Lake "The Trench" between Watson Lake and Prince George, is the most direct route for your destination. I'm not a big fan of the trench, although I've neve actually done it. You're down in a very long valley with little or no services and almost nothing in the way of Wx reporting. I'd be more inclined to stay on the highway to Ft St John, then go directly to Prince George. You'd require pretty good Wx to jump over the rockies there, but it's a lot shorter. JUst my thoughts, your results may vary. Make sure you have a good survival kit. Bring food and a sleeping bag. You could get stuck on a remote strip. Being prepared would make it a lot more plesant experience, almost like a camping trip. Not being prepared would make it miserable and make you more likely to press on into bad conditions.