Just my 2 cents: Have you considered going through Dixville Notch in NE Vermont and crossing into Canada at Canaan. It's a small border crossing and usually there aren't many hassles with boarder patrol. From there head north on 253 and then the 108 just before East Angus up to highway 73. Then stay the night in Quebec city and be sure to visit the old part of the city (oldest city in North America, circa 1604). From Quebec city to Forrestville, it's aprox. 5 hours (without stops)on the 138N along the St-Lawrence Seaway.
Being from Quebec, I can assure you that it's a beautiful ride.