Not sure if the factory head unit has pre-outs, my car came sans radio since I was pulling it out anyways. All you need is a line level adapter, they sell them just about anywhere that sells stereo equipment for like 25 bucks. All you need to do then is tap your speaker leads and run the hi-level signals in and it outputs to low level RCA's...easy as cake. The better ones have a gain control for each channel on them too to better balance your sound. And you can always just tap the back side of your fuse for the lighter for a switched 12V for the remote.....