Just a Short Note on the Kancamagus
Great Road! First, it's pronounced Kan-ka-MANG-us (with an 'n'). If you can, drive it from west to east, from Lincoln to Conway. It's a long steady climb from the east side to the top of the pass, while the western approach is significantly shorter. I once biked (bicycle) from Conway to the top of the pass and was completely exhausted. I also totally destroyed my brakes on the way back down, even though I was passing cars(!!) to try to save the brakes for the bottom. With an RV and a toad, going westbound on the Kancamagus could prove a trial.
AZBuck
Worth the Twenty Bucks or So
If you are going to be spending a lot of time on non-Interstate roads (not necessarily 'back' roads, but even some older US and state highways) you'll need a road atlas that shows where low clearance bridges are. For this I've found nothing better than the Rand McNally Motor Carriers' Road Atlas. It seems to get updated each year and is available in various editions (year/binding) from various retailers.
AZbuck