On a car I used to have I mounted the filter on the inside rail like I described above. The fuel pump was actually mounted on the inside rail but was on down the line a little toward the front of the car. I mounted it over the axle up where it would not be in contact with anything. It was above the bump stop over the axle. I guess you can understand where it was mounted. I also used thick rubber between fuel pump and inside of the frame rail. I drilled holes all the way through frame rail and bought bolts long enough to go through it and the fuel pump mounting bracket. I still had a little drone from the pump but it wasn't to bad. Those electric fuel pumps are some noisy creatures.
