I did this ride several years back, plus several thousand miles more in the Canadian Yukon and Alaska. Ended up at 5,000 miles. A great ride, but prepare for remoteness. I used the MILEPOST book to prepare for the trip, which contains a wealth of knowledge. I still have my route guide, town listings, and available grocery places if it would help you.
A couple of things about Northern Canada and Alaska to consider in planning: It's never dark in the summer. In late July in Fairbanks, I could read a newspaper at 2am. Many roads are gravel/dirt, though the Cassiar Hwy last summer was mostly paved now. The mosquitoes can be torturous at times.
If you seek adventure, this is a great ride. Just go prepared and enjoy the beauty!