There should be a small plastic cover in the upper left corner of the driver's footwell, that protects the location where the factory pigtail plugs in. You should have also gotten a 4 foot factory pigtail for setting up a trailer brake controller. On the pigtail, there should be a label with a diagram that will show you the wire pinout, as well as the location where the pigtail plugs in. If you didn't get one, you might want to stop by your local dealer, and inquire about it.
I don't know for sure if it is the same. It is easy to check out. Pull the large plastic shield coverging the under side of the dash. Look for a taped off 4 wire set on the left side above the kick panel.
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