I don't have the Holley pump on my cuda but when I had the pump on a Charger it was loud. I installed inner tube between the pump and the frame. That didn't work. I even put inner tube between the pump mount and the pump! Then I installed thick rubber(some kind of concrete floor mat that suppose to keep down leg fatigue almost a 1" thick) between the pump and it was still loud.... not as bad however. What I mean by loud is you can sit in the car with the engine running and mostly hear the pump buzzing.
Maybe the "new design" won't be loud.