I just went and found it for you. Its page 31 and newer.

Heres what you have to buy to connect to the factory gps antenna. At least its what I needed for my Seicane.

connector at the back of the radio
https://amzn.to/2DHXPwb

90 degree elbow
https://amzn.to/2Wr9VBc

Actual 20 foot gps cable
https://amzn.to/2sUTZcJ

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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
More are at my website

Aftermarket E53 Radio Install