George, I do not know a route for you, sorry. But I do suggest going to a library and using the Gazeteer Map books. Theyre big and have red covers. theres one for each state. They show all roads, even dirt, and are topographic which is KEY when planning a route.. especially when youll be covering over 100 miles a day. and especially in VT!!
To get out of NYC and heading north quickly, I suggest coming over the GWB and following NJ rt9 north into NY state, its a very popular ride for NYC bikers who want to put saome miles in and get out of the city. Do it on a weekend and youll see many other bikers that day. You're on your own from there. But try those gazeteer maps, they made my tour. I know that there is a nice ferry that crosses into VT (burlingotn) from NY state, across whatever big lake it is across from Burlington! (if Manchester is that far?)
have fun, why not make it 3 or 4 days?
~Steve