Per Dan Horton, I am installing a stainless steel support rib between the floor and the cooling ramp. The goal is to dampen / eliminate the floor drumming. I used some left over stainless measured off an inch of rib and 1/2 inch each for the tabs, cut it, then bent it in the vise. I made it a z-shape and then tested the fit it under the ramp. The idea is to glue it with the fire barrier - which will be an interesting logistical process. I can pre-glue one side, but the other will be glued at installation as it is hidden under the side bottom skins and there is no access. I might like it better as a c-channel so I might look at that process next time.
