There will not be a jack behind the radio the aux is usually for satellite radio or a factory installed 3.5mm jack. ford usually puts the jack right on the dash but it may also be in the console or glove box. I don't recall 06 needing the tools but if it does need it you will see the two holes on either side of the radio. The tool costs about 3 bucks at oriellys or autozone. Don't stick it in too far or you'll have tons of fun getting the radio out and may not be able to.