You don’t need the installation set which includes the lower steering wheel cowl. You just need the switch, part number 61316940989. There is an imprint on the inside of your existing cowl which you can cut out to fit. I recently bought a switch from LLLparts for around €103 plus delivery, which is probably the same as you’ll pay for used on eBay. It will plug straight into a 2003 E85, you will find a small loose connector on the steering loom.
