Problem I see with 83 looking on the map is that you will have to go between Athens and Atlanta which means either a lot of traffic lights or traffic.
Looking at Live Oak, FL location and figuring you are starting in Charlotte area or at least convenient to I-77. Combine this since you say you enjoy nice back roads. I've traveled most of these roads in the last several years and don't recall any bad sections. Except for the interstates, there are only a few bridges, none of which I can recall as being under 13'. Suggest you look at I77 to Columbia, Hwy 321 to Hwy 301. Take Hwy 301 all the way down to GA where you can pick up Hwy 84 which is one of the nicest dual lane-almost non traffic roads you will find in the country. Finally pick up 11/129 straight down to Live Oak.
