okay, here's the story. i bought a used fuel sending unit. the fuel sending unit that i purchased used, was not disconnected from the fuel pump, the wires were cut. i decided to go ahead and cut my wires and splice the negative to the negative and positive to the positive. i used butt-connectors with plastic covering. now, after doing it i'm afraid to put it back together. i do not want the rubber to spark or the two wires to touch, what should i do?