The rear speaker wires are located in the b-pillars. You wont need to do anything with the front speaker wires. It's a total of 4 wires you'll have to splice into. The rear seat is removed because you have to run wires underneath of it to get to the fuse box and the passenger side b-pillar. The unit itself comes with the wires to tap into the speakers, as well as one for power, remote and ground. I don't think the remote wire was long enough to reach to the fuse box behind the glove box though so I had to splice an extra remote wire I had laying around into it. I can send you a quick video tomorrow after work.