I went to a local stereo shop and bought a metra tech wiring harness for 12 bucks it is made for changing head units in a ford car with a premium sound system. My cobra is a 97 so i used the 12 dollar one. if you have a 94-95 i think you have to use a different one that costs around $20. If you don't have a shop that sells the metra tech harness just do a google.com search for metra tech, they have a 1-800 number and they will send you the one you need.