Again, the top boards are held into the woodwork with brackets at the ends. The original subwoofer tube is what you see in the corner. It's pretty sturdy, so the boards are also secured to that. The cross brace is again screwed into the woodwork and the board just above the speaker (I figured it would be easier to fix this than holes in the plaster). The ramp is held into the wall with three screws (the only attachment to the wall itself) and again screwed into the board above. Tim or I can hang from the brace and the structure won't budge.