The final thing your achieving is connecting #17 from the radio #5 with #5 being in the trunk since its moved there when you use the long cable Seicane provides

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Just BMW's - All cars and trucks was two pages long
1994 318is
1997 528i
2000 323i
2001 X5 3.0 auto
2005 X5 3.0 auto
2011 535xi auto
2013 X5 xdrive35 Turbo
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Aftermarket E53 Radio Install