well i dont know about your car but on my contour on the right side behind the brake fluid and all that down under there there is a small little tear shaped plug. Its about 1 inch by 2 inches, and if you pull it off and kind of poke through the material it comes out right under the dash behind the brake pedal and near the fuse panel. Then from there you can just run it under the side panel to the trunk or wherever. This is just what i did on my car i am not sure if it would be the same for yours.
