I am replacing the floor in my MC9 and came across three aluminum panels just forward of the engine compartment and under the plywood floor. MCI seems to call these panels a "Smoke Panel". The panels were not attached to anything. Should these panels be replaced when replacing the floor?
I would consider them a necessity with a name like that. Probably a heat shield to protect the plywood,
a sort of firewall so to speak.
I agree with Rick, my 4104 has the same thing just behind the mufflers on the firewall with about an inch separation between the panels and the firewall so air can flow behind the panel and cool it.