Fuel pump parked up hill

What do you guys do to deaden the sound of the electric fuel pump? I tried putting a grommet in the hole and 4 or 5 sheets of rubber between the pump and the car body.

There must be something to use that will not transmit the sound to my ears


is your pump a solenoid type pump or electric motor type? if its solenoid there should be minimal noise when running, if its electric good luck; there loud and annoying and I wouldn't have one (Holley blue pump and those type)