Hi, Rattybird I fitted one on mine if it's like mine there is a plug at the back of your fuse box but I had to run cables to the wiper plus a washer bottel I found it a bit of a fiddell. All my bit's cost £65 and as Rob said you dont use it very much I think I have used a bit more than Rob but not a lot. Hope this helps if you want to you can PM me.
Hobopatch
Or do what most do, remove the thing and just bung a rubber grommet in or a nut and bolt with two big washers each side. Chances are the motor has had it and to be honest they're useless as you don't get that much muck on back screen with it being almost vertical and its just as easy to give it a clean next time you wash van. This was mentioned some while ago on here - VW only fitted them as a 'luxury' selling point but in terms of usefulness, forget it.
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