[WKB]

Bob,
I used a polyuretane adhesive/sealant. Messy to use, but works well.
I sprayed both the foam rubber and under the guard.

Byron W,
I tried brushing and ended up buying a spray gun. As you would expect the finish was worth paying the money for. The equipment used fpr spraying sound deader was not that expensive. I only paid about $50 for mine and I have seen them on EBAY cheaper than that.