I am building a soundproof wall. It consists of metal furring channel, a layer of fire code 5/8” drywall, green glue in between, another layer of fire code 5/8” drywall. My dilemma is how to attach 3/4” pine 1 x 10 shiplap to this assembly. I was going to use PL Premium on the back and using 2” Brad nails into the drywall to hold till the glue drys. Does anybody agree or have another idea.