Fiberglass floor pan? questions...

[Daytwo69]

Hello everybody. I am in the process of tearing down my 69 Camaro for a day two style rebuild and came across something I didn’t expect nor understand. Hoping someone can help me out. I pulled the carpet up from the floor boards and found what appears to be fiberglass fixed to the floor pan where your feet rest in the front and back. It’s not under the seats or on the transmission tunnel just where your feet rest. The trunk floor is also completely lined in a mat of woven fiberglass. Anybody know why that would be done? I have laid under the car and the metal floor boards from under seem to be intact with no major rust holes. Could this have been an attempt to suppress heat or preventative measures from potential rust problems in the floors? This car is destined for a body off resoration but I hate to think I have good metal to work with then get it to the blaster just for them to tell me the body has nothing left worth saving. I know there are cancer issues under the back glass, windshield, front fenders and maybe one slamm section on a rear quarter panel. Appreciate any and all input.