As a result of discussion in the topic below, I took a look at some NC routes a found a few more points on the below routes that applied. It looks to me that there a probably a few more throughout the state that should be looked at while fixing other files in the future.
http://tm.teresco.org/forum/index.php?topic=125.0(Mike-Note I am not sure if you had done any of these already (especially the ones involving US 421) so I posted them all):
NC 55- NC 11(Posted N-S), NC 50 (Posted N-S), and US 421 (Posted N-S)
NC 50-NC 403(Posted N-S), NC 41(Posted E-W)
NC 42-NC 55(Posted E-W), NC 22(Posted N-S), NC 58(Posted N-S)