To install an MKIV computer in the 5 series, you have slightly more work to do.  The below images are courtesy of Thor

----ALWAYS DISCONNECT BATTERY when removing parts from BMW--------

Warning, make sure that you do not disconnect the battery if the light is still ON the navigation computer.  Iit is a good procedure to follow on all BMW nav computers.

Starting viewpoint

Remove the access panel

Home made computer removal tools from coat hangers.

Insert the tools in the computer and remove the old style navigation computer

Remove Navigation computer

----NOTE The antennas are in the picture above FIT the navigation computer but are WRONG.  The navigation comptuer needs the antenna from the GPS module behind some of the brackets.  This antenna goes between the bottom of the CD changer and the top of the black DSP amp on the sidewall.

Notice how this cable goes to the DSP AMP.  It is a digital audio link from your CD player and not the GPS antenna connector.

To get access to the GPS RF connector you will need to remove the changer.  To remove CD changer, loosen the two screws on the right side, pull right side free 1/2 inch and then lift right side slightly and tilt to the midline of the car.

Remove the Left CD Changer bracket

Remove the Navigation computer bracket

Remove the Right CD Changer bracket

Remove the Vertical bracket

Remove the DSP Amp.  To get room to remove the amp the silver Alpine unit needs to be moved to gain clearance. At this point the Alpine can be lifted free of two drop in brackets and pulled towards the inside of the car. This gives room to pivot the amp counter clockwise with some maneuvering to clear the attached brackets. This reveals the Trimble unit, the antenna lead and data/power leads into it.

all components removed and antenna lead shown hanging down the middle

THIS IS THE GPS MODULE.  You need to remove the RF cable from this module and plug it in the back of your new MKIV navigation computer.  You can then just tape off the power connector and leave it to dangle in the rear of your car.

Installation is reverse.  You will no longer need the Trimble GPS module as a GPS module is built right into the MKIV navigation computer.

 ******IMPORTANT.  If you are installing a NEW MKIV, once you install the hardware you will need to upgrade your software.  After installation the navigation computer will prompt you to insert the software CDROM.  If you purchased from BMWNAV, The latest version of the BMW software CDROM should be in your shipping box.  See link for download and installation details