I don’t have the rib racks, so I looked at the photos on the store site.
Seven racks, on their side will fit. The design is so the ribs don’t fall, two higher sides on left and right provide stability. Just the design.
I’m not sure if that is what you are asking though? You don’t have to use the holder though, especially if you aren’t smoking but a few racks. Just place them meat side up, maybe two racks per shelf? I have a #3 and that’s how I smoke them. Not sure if a full length fits in a #2 so cutting in half and laying them across is fine as well.
Hopefully that helps. If I misunderstood your question, I apologize.
Enjoy the ribs!