Bruce,
See Dan Goldenberg's bike storage solution (http://www.mindspring.com/~d.g1/storage.htm)
He hangs them up vertically by the wheels, alternating every other bike's orientation (first one front wheel up, the next one rear wheel up, and so on). The hooks are staggered every 16 inches, so his method is slightly more efficient then your ~19 inch spread.
Or, you could simply use my storage method: take a relatively unused room in the house (like our dining room that's been converted to my wife's music room), start stacking up the bikes as they await their turn at cleaning/restoration in the garage, ignore the inquiring looks as you wheel in the latest acquisition, and maintain your innocence when a new scratch appears on the piano...
Hope this helps,
Ian "But honey, I've hardly got any compared to some CR'ers" Kersey