Stephen, in the picture posted by Bill: You need a wire connected under one of the mounting screws on the flange to a good ground.
Then the top terminal goes to one post of your gauge. The other post on your gauge should be hot when ignition is on. NEVER put a ground to this post or the top terminal on the sending unit.


57 GMC LCF 370
55 John Deere 40-W
59 John Deere 430-W
2000 GMC 4x4
56 John Deere 420-W
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