Don't give up. Just rip it apart and line it with copper foil. Anything is possible.I've given up pretty much on a Corvette
Tapes Master 2", 3", 4", 5", 6" x 36 Yds Copper Foil Tape - EMI Shielding Conductive Adhesive tape (6 inch)
Amazon product ASIN B01L16U4KM