Watch the Drop 3, 4 Voicings: online guitar lesson by Brad Carlton from Guitar Lab: The Golden Arp
There is only one form of the drop 3, 4 voicing of the add 9 chord in 2nd inversion. It is derived from the 2nd inversion close voicing and ends up being played on strings 1, 2, 5 and 6. This will require a bigger "split" in your picking hand whether you are finger picking or hybrid picking. The video demonstrates the importance of an upright finger posture of both the 3rd and 4th fingers. A grand barre of the 1st finger assists this positioning.