Here's a BBB picture I have. You can see a few things here.
1. In the lower left, there is a board that isn't in PM that means the OCD would have to mount higher up.
2. The fluorescent tube bracket looks like it may force use of the right column of standoffs with a narrow board and adhesive standoffs on the left edge.
3. Frankenstein LED OCD installation based on the Sys11 design.