In the absence of that clip on jumper, you can run a jumper wire from one of the screws on the tank body (_NOT_ the gauge connection) to any convenient point on the chassis or body. With the clip-on jumper, clean the clips and the metal where the clips connect, and maybe just tighten up the clips a bit. The clip jumper just completes the ground circuit from the tank to the metal fuel line. The metal tank body just has to be grounded. HOW isn't really important.
BC
