I just mentioned the rear wheel well humps because when I dynamatted my VX I originally did just the entire driver/passenger area (bottom, top, door, door) and the rear floor of the VX.

Turned out that most of my road noise was coming from the wheel wells (really bad). Especially with the seats removed, it just resonated. Kind of defeated the purpose if I still had noise, so I had to buy more to cover those... It helped immensely.

Best of luck.

-biju.