How shared can a chart of account be in Release 11.5.10?

 We have a management directive to meet which says that we must "share" our chart of account with another legal entity as part of a shared services arrangement.

At the moment, our Chart is 3 characters shorter than their but the same number of segments.

I'm looking at 4 options:

- don't do it,

- just change ours to look like theirs by lengthening two segments and

 - don't do it but make a few cosmetic changes such that we can use similar reports to them which is actually what the management want!)

- retire our existing set of books and move into a new set of books which uses the chart as set up in their set of books. I realise this is a reimplementation but what I want to know is,