Two suggestions, depending really on whether this is a one-off or an ongoing
requirement.

For a delta document that keeps 'in step' with the master, Maintain the
master with the proposed 'deleted' chapters with hidden font. When you print
or display without hidden text, the numbering and the contents will show
only the unhidden sections. In Word XP the numbering will however reflect
the hidden text numbering. When you want the full document text, take the
option to print hidden text, or run a macro to remove the hidden attribute
(don't save, or do this on a copy to maintain the original marking).

Alternatively, take a copy of your master document and convert the numbers
to text before editing. You can do this by typing

ActiveDocument.ConvertNumbersToText

in the immediate window (Alt-F11 Ctrl-G).