stock head unit

The stock head unit does have a connection plug for rear speakers.
The fader control also will control added speakers. It does not have any rear speaker harness attacked to it.

--You need to connect your own wires to it using pin plug connectors you can get from an auto parts store. Also you need to reattach the one green wire from the factory female plug.

A easy way to add speakers is to purchase indoor/ outdoor speakers like I did. There is plenty of room behind the seats to install this type of speaker. Size and quality depends on your wallet.

The ones I used are from Radio Shock. Avio @ 29.00 dollars. They sound OK. Definitely add what is missing to the stock sound system.
May upgrade in the future. But am more than satisfied for now.

Hope this helps....

-