According to the guy doing mine it's just a case of taking the lock off, welding a plate over the hole then a wee bit filler, and then painted.
As I said to Ac!d, dunno how much he's charging me just for this one thing. Which might not be getting done now, since they can't remove the boot spoiler. Spoke to the previous owner of my car 2 years ago & they said the only problem they had with it was a water leak into the boot. Apparently it was back to the dealer 4 times to have this looked at, and the bodyshop are now telling me that it looks like they have bonded the whole underside of the spoiler onto the bootlid to fix the water leak. This means that to get the spoiler off will probably result in the bootlid or the spoiler being damaged (or both). []