Audio Systems: 1998 Ford Taurus, channel amplifier, ford taurus

Question
Ok, so I have a Taurus with factory stereo that I would LOVE to replace...unfortunately all of my controls for heat, fan speed, a/c, etc is digital. which means there isn't a kit so I can install a new stereo :( So I was wondering if you happened to know what the specs on the amp that is located in the trunk of these cars. And if there's a way to hook another amp to it so I can have my subwoofer and other speakers powered. So to clarify, my question is, what are the specs on the already installed amp? AND is there a way to install my speakers off of this one?

Answer
the unit is 17W rms X4 YOU CAN buy a jbl 5 channel amplifier that will give you
25w rms x4 and 1 digital sub woofer output this amplifier will use the same controls at front and cd changer

or  you can rewires the amplifier you have and add 2 of this
http://www.oemautosound.com/pc-575-132-pie-2-channel-high-to-low-converter.aspx


you will need a 4 channel amplifier and a separate amplifier for the woofers