[DeTomaso] Fuel Tank Guard question

[Tom Borcich]

Just removed my fuel tank guard so I can seal the inside of the fuel tank. 

Is the guard aluminum or galvanized steel? It seems to be two layer with 
something in between the layers to act like a heat shield?  Not sure if I should just 
clean it up or paint it.

Is there any reason to add some additional heat shielding matt to the tank side of the shield? I 
would assume the heat shielding material today is better than what was available in 1972.
 
Tom