Just search for Hualingan, Dynavin or navigation, lots of info for you to read. You have to cut the bracket out, so once you cut it out there's no going back, I had to cut mine to install my Hualingan unit.

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2002 X5 4.6is
1999 C5 Corvette
1992 Mitsubishi 3000GT VR-4
1994 Kawasaki ZX-9R
2005 Mazda 6 Wagon (Wife's)
1991 Mitsubishi 3000GT VR-4