I think I figured 26.5" for normal black disconnects, and the line coming off it to be able to curve at a normal angle.
I know they have some low-profile disconnects but I couldn't tell you how tall they are. maybe save you a half inch?
Primary: English Mild
On tap: Pale Ale, Lancelot's Wheat, English Brown Ale, Steam Beer, HoovNuts IPA
Bottled: MOAM, Braggot, Raspberry Melomel, Merlot, Apfelwein, Pyment, Sweet mead, Cabernet
Gal in 2009: 27, Gal in 2010: 34, Gal in 2011: 13, Gal in 2012: 10