Well you certainly need a sender, and I hope you have that. Run a wire from the connection at the sender to the "G" on the gauge. Also run a ground from the sender screw attachement to the earth or ground symbol on the gauge (NOT "G"!). Then power the "+" off the fuse panel and the ground should continue from the gauge to the instrument ground screw on the center console. You also need gauge light by splicing to the brown instrument wire in your dash to the tiny light bulb. The other side of the bulb socket needs to be part of your ground wire complex.