I recently pulled a head unit out of a junkyard...it's a JBL cd changer/cass part number F67F-18C852-BA, I'm pretty sure it came out of a 97 Explorer...I figured it would fit into my 99 Explorer Sport, but I do not know if I need a certain wiring harness or if it's just not going to work at all and be a money pit...What I am trying to do is take out my factory unit because it stopped working and put this new unit in....Please get back to me with any help, not a novice with these audio units, so anything will help...Thanks Chris

http://oem-auto-accessory.com/factory_ford_radios.html

check all the pages linked on the top of the page also. Much info there.

If you did not have a JBL system in your truck, the JBL head unit will not correctly work with your Ex, you do not have all of the harnesses needed to correctly run it.

Post the part number of the radio you took out and that will help.