Electric fuel pump mounting?
Funny thing. After I saw this thread it got me thinking my pump was really loud.
I looked at it today and sure enough...I hadn't put the rubber washers on it when I put it about 8 months ago.
Couldn't find the washers so I cut some leftover rubber hose, first to length, then split it open down the middle, then drilled holes for the mounting bolts. Lots quieter now!!