Watch the Six Days online guitar lesson by Joe Dalton from 50 Country Guitar Licks You MUST Know
The rhythm figure on Dave Dudley's Six Days on the Road had an electric rhythm part something like this one. Adding the g and b notes to the A chord makes it an A9th. This figure has blues notes and movement to it. It also has a certain bite that helps to drive the music. You will hear the descendants to this in many modern country songs.