Hi Nigel.
Im not sure what the plan is, the small extract is the extent of my knowledge on the matter at the moment.
I think it needs the whole roof at 'the doors' to be raised, as it needs the scaffold rigs to be able to be put alongside the tail.
Its a large amount of modifications which seems a lot for 1 aircraft type, but I suppose a few paint hangars around the world need to be modified eventually otherwise there will be nowhere to paint them in the future, unless they take them back to airbus?