Nope, navigation does not matter. Though, it does affect the location of the radio module. In a non-nav car, the radio module is the thing with the tape or cassette slot in the dash. In a navigation car, the radio is a non-descript silver box in the trunk with the amp, nav computer, and other related components.

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SOLD
2000 E38 750iL Highline Edition, Upgraded with the lastest 2006 X5 Electronics
MKIV Navigation, 16:9 Display, Bluetooth, TV/Video with Backup Camera, Sirius, and Aux Input