I would use something like the Three.1 mentioned. You have complete control over the sound coming out of the device that way.
Then you can pick up your factory head unit from Ebay or a forum and return your car to 100% stock look. Mount the eq in the glove box. Nobody would break into your car. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif