Updated 2014-03-13 WB

Make sure you have the partial checkouts as shown in element-count.sh:
http://www.wonkity.com/~wblock/replaceable/element-count.sh

Run the script for a report.  Sample shown here:
http://www.wonkity.com/~wblock/replaceable/report-2014-03-12.txt

The devel/diffuse port makes it relatively easy to compare the old
version with the new one:

% diffuse pre-db5/books/fdp-primer/working-copy/chapter.xml doc/en_US.ISO8859-1/books/fdp-primer/working-copy/chapter.xml

Use ctrl-F to find <replaceable>, compare to the current version on the
right.  If <replaceable> is missing on the right, and the format has not
changed, highlight the differing section on the right and click "Copy
Left Into Selection".

If the format is different, manually add the <replaceable> and
</replaceable> tags on the right.

Click on the left side again, and use ctrl-G to find the next instance,
and continue until the end of file.

A list of files that I have repaired is here:
http://www.wonkity.com/~wblock/replaceable/done.txt

Please notify me (wblock@FreeBSD.org) when you fix any of the others.  Thanks!