How does the fuel sending sending unit sent the signal to fuel guage on a 71 dart.

I grounded the sense wire and it shot up to full. I did the ohm test on the sending unit and got 62.7 ohms which may be right. I only put $10 of fuel when I take it for cruise cause I don't want the gas to run out. I also tightened all 4 nuts behind the cluster. I even ran an extra ground wire and clamped it to sending unit. The real test is when I put gas and hopefully the guage will move.Any other suggestions on what I can try? I'll let y'all know when I put gas in wich should be in a 1hr 1/2.