Sorry to delay - I'll check tonight and post.
The key is to space the hangars for the basses YOU own. If you have a Casady bass or similar hollow or semi-hollow basses, you will need to space the hangers farther apart than if you have EB-0 or Mustang basses. And if you do two rows, don't forget that headstocks have tuners sticking out of at least one side, often two. If the bodies of the basses on the top row hang down into the area where the headstocks on the row below are, you need to space the bottom row out farther to keep the bodies on the top row away from the tuners on the row below. (Note the tuners on the Casady and the Univox 335-style bass in the photos below....VERY close to the body of the bass in the row above.)
And don't forget the scale length of the basses and the length of the headstocks. Fenders have long headstocks. If you're mounting near the ceiling, you need to make sure that you not only have room for the headstocks, but add 3-4 inches of room to lift them off the hangers! You don't want to bang the headstock into the ceiling every time you pick up a bass.
Conversely, if you do two rows like I did, make sure that you have enough room on the bottom row to hang a 34" scale bass and not have it resting on the floor.
My setup wasn't perfect, although I managed to move basses around until it worked. I did have to be careful not to chip the bodies of basses on the top row on tuners of the row below. I was trying to get a LOT of instruments into a small area.