Watch the If 6 Were 9 online guitar lesson by TrueFire from Play Acoustic Guitar 4: Rhythm Principles
If 6 Were 9 - Overview is a video guitar lesson presented by Brad Carlton and is sourced from Chord Studies: Open String Chords Vol. 1.
This sweet little progression is played with 4 open voicings; B madd4, F# m11, G 6/6 and D sus2. Again you're faced with some challenging muting but the payoff is well worth the effort. Work out the pivot and guide fingers that feel most comfortable for you and keep those open strings ringing!