Apparently Boeing has a tech team who goes around and does major repairs in the field. National Geographic had a show which documented the replacement of an aft pressure bulkhead on a 767 by removing the aft sections. I found it pretty interesting. Course, on this one you can't use 5,000,000 rivets on this to put it all back together, but generically it wouldn't be the first time that they'd split a hull at a seam, done work, and put it all back together somewhere other than at the factory.