i`m sure i bought two of the 69 stang units but i cant find the second .. i wanted to post a picture of it and show you the little tab that needs modifying .. anyway my new stang unit has only one gas line and one wire hooking up to it ,, my eyes are so poor i cant tell for sure what color the hook up wire is but i think it is brown with a white stripe .. you need to fix the end of that wire so it will plug onto the single sending unit outlet .. the other factory pinto wire looks to be black .. it must be a ground ..i just clamped it to the metal fuel outlet line on the unit ..a new unit will come with the o ring and lock ring ..my gauge is`nt perfect but it will work and keep you from running out of gas ..