Hey i have a 66 chevy truck and i just bought an under the bed gas tank. the problem is that i can't figure out how the sending unit and lock ring are attached to the gas tank. I bought the gas tank from gmc pauls, if that helps any. Also what is the best way to run so that i can fill the tank up from inside the bed. can i buy a kit to do this. anyhelp would be greatly appreciated. thanks