ok i have a 98 with the monsoon system. i replaced the headunit with a pioneer. i wired it up like i have many other cars using a metra wiring harnesss. my speakers in the backseat dont work at all. was i suppose to wire something differently with the monsoon. i didnt even look at the factory harness because i figured it would have the same wires as all the other cars but i guess it could have more wires for those speakers. so do i need to tap into them if so?