Watch the Truck Stop online guitar lesson by Joe Dalton from 50 Acoustic Blues Licks You MUST Know
In this example, you can see how the simple addition of a pull-off can change the entire feel of the lick. You can use the same idea on each of the other voicings. The pull-off to the open E string works harmonically because the E note belongs to the E and A chords. Keep all of the other strings sustaining.