It connects directly to the cd changer plug, without a problem, I made up a small t piece lead so that I could have a connection without having to remove the cd changer every time.

Cost was about £6 - £7 or so for the bits and about 1/2 an hour to make up and install.

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Sept 03, M3, Silver Grey. Retro-fits: Modded Mk4 DVD Drive, OEM Bluetooth, VR Control, Rainbow Speaker Upgrade, Sony SOT Amp, HK Sub, CCFL, Intravee II, NightMode.