Connecting a Amp Line-in to Stock HU?

I am going about trying to find a way to save the $220 on a new head unit for the moment but I want to hook up the subs and and amp that I have got already so I can get some nice bass out of my truck. I have everything pretty much figured out I think but I don't know what I am to do about the actual hooking up of the line-in on the amp to the stock head unit I have. I have a 2001 Ford Explorer SportTrac. I was thinking that I may be able to splice into the lines running to the front left and right speaker (or rear). What problems may I have in doing this? Will it even work? I also read something in another thread here about something called a Line-Out converter (never heard of it). Is this something of use to me to do this right? (Also I wonder on the amp to turn it off when I key off the car I would have to hook it up to the 12v Ignition connection on my stereo (or if not tell me what color the wire is and ill go from there).) Thanks. -Fish

OK so I have read nothing that says that wiring it directly to the speakers would kill anything... But a Adjustable Line-Out Converter definitely sounds like what I need to help prevent the rest of my stock speakers from sounding horrible. Of course if I wire it up directly and it does not sound like crud then no worries. :P (I sure hope my local RadioShack has a Adjustable LOC) Also the fact that some LOCs have the remote connection on them would make my life easy. But again I think that the "12 volt ignition wire" on the stereo harness will work in the same fashion. Sorry for the the 500th new thread about wiring amps to stock systems before researching through the forum. :P

You're headed in the right direction. Pickup an loc at a local stereo shop. I prefer to use an accessory (rather than ignition) wire for the remote, since it will also turn on with the key in the accessory position.My ex once told me I have a perfect face for radio.