I am replacing my fuel pump. The TR3 Owners Workshop Manual in chapter 3, section 6 speaks of a slotted nut on the rear stud attaching the fuel pump. My fuel pump is not working, so I removed it to install a replacement pump. The rear nut is identical to the front nut: no slot. Can someone tell me or show me what this slotted nut looks like, and why it is slotted? The Manual makes a point of returning this slotted nut to the rear stud, but the fuel pump used to work fine the way it is. Moss catalogue does not list a slotted nut.