I cannot believe how quiet my GTX is now. I sprayed both lizzard skin products wherever it made sense to spray, which to me was...everywhere I could reach that was not a finished surface.
I am running Dynomax VT's on 2 3/4" stainless pipe direct off the stock 5.7 exhaust manifolds.
I am WAAAYYYYYYYYY happy with these results, try it, you'll like it