factory system interfacing with a loc

No they also make 2 channel LOCs. You still splice into the speaker wires and then plug your RCAs into the LOC. An LOC takes high level inputs and converts them into a low level signal, that way you can run any amp, including a mono block or 2 channel. A 4 channel amp is not a neccessity in order for a sub amp to work with a factory system

razorbacx, no problem man glad I could help

i must be retarded, because i still don't see how that allows my speakers to work like normal?? If i splice into the stock speaker wires and run them through a loc how can they return to the speakers without me running all the wires from an 4 ch amp back to them....or is this what people are talking about when they are looking to tap into a rear speaker?? just use a two channel LOC? 

Can I use a 4 channel for the time being and only use two of the channels if that is the case?  Thanks again to everyone helping me out.