I know there are already several guides on retrofitting a RNS-E, but they all have an OEM HU. I have an A3 8P of 2003 with a non OEM HU and I would like to retrofit a RNS-E. Can I just use the kufatec adaptor or do I need to do some wiring? If I do need to do some wiring, is there a wiring diagram?

Thank you.