I hope this is the right section, its kinda more car audio then carpc so I figured it was.

Well, I am just about ready to put the first version of my carpc in my Explorer. I would like to totally eliminate my h/u and just use my pc. Well, I'm not quite ready to buy a new amp however. I have the factory JBL amp currently and would like to use it in my setup. I also have a an amp for my sub. I need to know how to hook a 5.1 sound card up to a setup like this?

I know the sub will be easy as I can just a 1/8 to rca connector and run it into my amp.

Now for the other four channels I am a bit confused. I know I need a line converter in between the factory harness and my pc but what should I use to go from 1/8 to speaker wire? Obviously each channel I need a negative and positive.

I am guessing I will have to buy something and slice it up but what EXACTLY would you recommend that will give me the best quality possible?