Yes it can be done. If you aren't familiar with creating code though it will be a very large learning exercise.

The tricks are how to get the sequence right and how to identify the chunks (your #3 & #4 steps) CONSISTENTLY. Typically, across 200+ documents, the variation across those files will make it very hard to arrive at a foolproof way of identifying the sections to include. Did you have bookmarks, headings, fields, content controls or some other way to identify content ranges accurately. Are you 100% sure the macro will find those 100% of those parts accurately - if not, what should the macro do?

To try and standardise things better, in the case of header content, I would NOT transfer the whole header. Instead, I would make sure my template includes placeholders for variable content (like mapped Content Controls) and then populate that metadata. This will greatly assist in your ability to make sure all docs have the same header layouts.

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Andrew Lockton
Chrysalis Design, Melbourne Australia