I was told many years ago that a Shackleton had a medium KERRUMP the other side of the pond. It was adjudjed repairable so it was entrusted to Avro (Canada) to be rebuilt. This they did and when they skinned it was fixed in the North American system using flush rivets instead of the good old British domed variety.
This gave birth to the one and only GT Shackleton, Thia one could now go 25-30 knots faster than all of its siblings. No problems unless you used it as a formation leader.