Installing sub in 2003 Straus SXT

I need help installing a subwoofer in my new 2003 Dodge Stratus.  My should be a simple case, but I have no clue what to do.  And am eager to learn and fast to learn.

Equipment:    1  12" subwoofer in enclosed case (in trunk)

                         1 200 watt pioneer amp ( mounted on sub case

                         1 Dodge Stratus 2003

Questions:     Where should  I put the ground wire?

                        Where do I hook into to get an audio signal?

                         How do I hook into radio control (behind dashboard)?

                         What's the best setup for maximizes my equipment?

The best way to do this is to get a amp kit you will need a 8 gauge kit you can either look on eBay or here http://www.knukonceptz.com/detail.asp?product_id=KOLAK8 but don’t pay more than $20  it  will supply you with almost everything you need . The only thing you will need to buy will be a high to low converter like this http://www.crutchfield.com/cgi-bin/S-ZX4988ox9pJ/ProdGroup.asp?c=11&g=721&s=0&cc=01 now you will need to run the power cable directly from the battery (must be fused within 18 inches of battery) to the amp in the trunk. This will supply you with your + 12 volts. Now your ground must be no longer than 18 long. You will need to ground it to bare metal some were in the trunk. The best thing to do is find a metal spot in the trunk next to the amp and sand it down till you have bare metal. Then with self tapping metal screws screw your ground into the location you have prepared. Now be sure you are clear of the gas tank and make sure you don’t drill thru any external body panels.  You will also need a remote wire this turns your amp on and off with the car. You will need to find a + 12 volt switched ignition source. You will then run that to the remote connection on your amp. Now for the signal you will need to tap into your rear speaker wires. So locate your speaker wires and connect the wires from your high to low converter to them. Make sure you have the polarity correct + to + and - to -. Once you tie that in you will connect your rca cables to the other end of the high to low converter. From there you run them to rca input on your sub amp. You will now have both power and signal going to the amp. Now to connect your sub box just run speaker wire from the signal out to your sub box and you should be up and running.  Here is a link to a good article explaining how to do all this. However it’s a little different than your install since you need to get a signal from a high to low converter on your back speakers rather than having an aftermarket radio with rca connection built in http://www.crutchfield.com/infocenter/S-ZX4988ox9pJ/car/amplifiers_install.html