Can't remember the exact route we've taken but I don't believe there are any low overpasses to worry about. As far as OBX goes after mid-August things quiet down. If you are concerned call a campground or two and see what their bookings look like. If they've got plenty of room then I wouldn't worry. If they are getting close to capacity then you might want to consider a reservation.
I may not have gone where I intended to go, but I think I have ended up where I needed to be
Douglas Adams
[purple]RV-less for now but our spirits are still on the open road. [/purple]