Lizard Skin...yes, why didn't I think of that. So, now here is my plan:

3M Body Shutz: underside of cab and wheel wells. Literature lists sound control as primary capability. This will eliminate need for any product on interior side of cab floor.

Lizard Skin SC (interior application): back wall of cab, under fuel tank, under seat (subwoofer will go under seat so better sound control is a bonus here), roof, and toe kick/firewall. Lizard skin is paintable, so I will apply before cab is painted and paint the Lizard Skin with cab finish (color) coat.

Dynamat: Inside of doors. Easier application than spray on product due to limited access. I like the mass of Dynamat to dampen the big drum that is an AD door.