You can't exactly keep them the same, unless you are totally done editing
and you want to convert them to plain text that will no longer update.
You can recreate the doc in a way that lets you do what you want. A couple
options.
1) break the doc into chapters, then use RD fields to build a TOC from
several files. See here for detailed instructions, though I'm not sure if
that includes the index.
Creating a Table of Contents Spanning Multiple Documents
http://pubs.logicalexpressions.com/Pub0009/LPMArticle.asp?ID=148
2) break the doc into chapters, then use IncludeText fields to create a
combined doc that pulls the text from each chapter (to create an IncludeText
field, start a new doc, and use Insert | File for each chapter, but be sure
to check "link to file" in the Insert | File dialog). Then you could
generate the TOC, index, and page numbers in the combined document.
Both these options pretty much require that you be familiar with styles and
templates, I think, so if those are unfamiliar terms to you, post back. But
presumably you are already using styles in your long document.
If those don't work, if you explain the end result that you need and why,
others may have better suggestions.
As Jezebel said, *do not* be tempted by Master Documents, although
supposedly they exist to fix this problem.
DM