A: Always disconnect the negative battery terminal first when removing cables to avoid shorting the battery. Even if replacing the positive cable, disconnect the negative first. Remove old cables from the battery or mega-fuse terminal, noting their routing for correct installation. If replacing, buy identical parts using old cables as reference. Clean solenoid or ground connection threads with a wire brush and apply corrosion inhibitor. Attach the cable securely to the solenoid or ground connection. Ensure new cable reaches the battery post without stretching before connecting. Connect to the positive terminal first, then the negative.