I'm trying to put a stereo in my contour and I looked up the wire colors and it says something like brown/yellow for like the positive but there is a brown and a yellow but not one that has both on it
If your harness is still intact just use a harness to install your new radio. It's much cleaner and way easier....
If you want to integrate the factory amp. - http://www.metraonline.com/part/70-5511
If you want to bypass the factory amp. - http://www.metraonline.com/part/70-5514
For the bypass option you'll use the gray adapter and then cut the black to black adapter in half. One end should fit the output side of the amp. Get some speedwire and extend the speaker wires up to the radio cavity and attach to your radio's harness. Route your wires out of the way and zip tie. Super simple.