Maybe use the transition libraries? Though I don't know if there will be problems anyways due to it being such an old version and that's assuming there is a version for AC 11 in AC 14.
When I work on older files, I find it's easier to just load that library instead of loading the AC14 one. In the case I do have to load the 14 library, I place the object I need then embed it so I can disconnect the 14 library later (embedding is one the really cool advancements in AC 14).
You could select all the objects that are the same all at once, open the objects' properties and navigate to the updated part in the AC14 library and ctrl-alt-click (bring up the syringe) before clicking on the updated part. What happens is it will inject the parameters of the selected objects into the updated part just like how the syringe works in the model space, and replaces all of the old objects with the newly updated one plus with the newly injected parameters.
I've had mixed results with this, most of the time it breaks the object but it's something to try.
My experience has been that if I want an updated part in place of an old one, I have to manually place the new part and adjust it to look like the old one, then delete the old part and replace it with the new one. In other words, yes, it's the hard way.
But I'm not a guru either so I could be proven wrong in the following responses.
