I have finished retrofitting a RVC High to our SII estate. It was a project with long planning and the parts gathering dust on the shelf for almost a year. Had a few days off and did not want to rush it.
I tried to read as much as I could on the net and used Bronken and Lutz's video ( Briskoda or Youtube) as a guide but modified my installation a bit.
The parts I used were:
Boot handle RVC 5N0827566AB - Passat
RVC controller 7N0907441 - Sharan
Cable from Columbus to RVC STG