
Hi there...yes, I did the upgrade year before last, or to be more precise, the boys at my local VW Independent Van Centre did.
I purchased the same (or similar) set you provided a link to. They removed the front bumper, fitted the fogs and carefully sealed around the back of the lights, sorted the wiring (nice neat job) and sited switch and the 'red light' to indicate that the lights are on, near the dash light switch.
You can purchase the 'proper' switch from VW and wire the fogs into that (as they would do if ordered from the factory), but it was another £80+ so I used the switch which came with the light set.
The main problem was cutting the bumper to create a nice smooth aperture for the light frame and seal to fit into...basically, you have one chance to get it right! I think they practiced on an old scrap bumper of the same thickness and material to discover the best way to do it.
Another difficulty was ensuring that they pointed in the right direction, once settled in their frames and sealed, so as not to cause 'glare' to other road users.
I think they look great and I do tend to use them as 'running lights' in low light conditions as they are much brighter than the side lights, as you can see from the photo.
Hope this helps.