If you're also getting the front bungs done then you'll also have to remove the front silencing material that covers the entire front section of the car (underneath the pedals) as it blocks off one of the bung holes. In my case this was extremely soggy from water getting in (well in both cases - I'm currently sorting out my second golfs floor).
There's a very annoying plug which takes a 13mm or 14mm or so allen key to undo, didn't have one so the first golf I had to use long nosed pliers to twist it round to unscrew as it was so well screwed down - I now need to sand the rather rough chewed look to it. Second golf just unscrewed by hand, so hope for that kind

My first golfs floor should be being welded this week (it's the worst of the two) and I was told that it would help if I were to cut away the underseal from around the holes (what little I could do I used scissors for).
I'd already removed the silencing material that VW use over the floorplans using a scraper and heatgun so you may wish to do that.
I also removed the pretensioners etc but I'd personally leave that to a mechanic (as a matter of fact in removing the passenger seatbelt I accidentally dropped the shoulder section down through one of the bung holes and onto the ground outside, holding a pretensioner while trying to pull a seatbelt back through a hole in a chassis is not my idea of fun!).
Chief
