OK guys,, here goes.
If you have a fuel-pump noise problem, the place to start is with your dealer or automotive service person. They can determine if there are any service bulletins that apply to your car. This is especially true if your car is in warranty. In all cases, all work on vehicles should be done by people who are qualified to do the work and who are familiar with the vehicle. Gasoline tanks can explode if not serviced properly, so this is not a job for a backyard mechanic!

The ideal place to install the filter is right at the pump, which is inside the fuel tank. It is electrically possible to install the filter on the leads where they enter the tank, but if the tank is not well shielded, electrical noise could still be radiated by the leads between the filter and the motor. On lower HF, however, this radiation will be minimal and it may be possible for your dealer to install filters to the wires external to the gas tank.

Hams have reported various degrees of success using various filtering techniques. In some cases, ferrite inductors have been added to both wires feeding the fuel pump. It is usually more effective to use a separate choke for each wire. In general, at upper HF, one of the split bead types can be used, with a couple of turns of wire on each bead. At lower HF, it will be necessary to use a ferrite toroidal core, perhaps an FT-140-43, with at least 10 turns of wire. In addition, it may be necessary to try a 0.01 uF capacitor across the two wires, perhaps on each side of the chokes. Some have reported good results using just the capacitors. There are also mechanical considerations. Splicing wires can result in mechanical failure, or corrosion, with the result being a motor that will not run (these things seem to happen at the worst possible times!). In addition, heavy chokes or capacitors can vibrate as the vehicle goes over bumps, ultimately causing the wire to fail.