two dents on the hood
 

i have two dents on the hood. one is about 6-7 inches in diameter and the other one is about 3 inches in diamater. i am gonna try the dry ice method first, but if that doesnt work, i have to either tap it out from behind or use the screw method. my question here is...and i guess its a protective firesheet under the hood....but how do i get that off? thank you