I have done this to my cab I sprayed the floor inside and out with dp90 then I put the dynamat down on the inside Then I sanded the dynamat with 40 grit and sprayed the floor with boxliner. When I was test fitting my seats in the truck I drug them across it and there did not seem to be any problems with adhesion I am covering my floor with carpet though. Check out my build pictures for pictures of it
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