Duplicating multiple accounts

[jmk]

I am in need of duplicating a large set of accounts ... copying them as
sub-accounts as a different base account in my GnuCash file. Basically,
I need to do this:

http://gnucash.1415818.n4.nabble.com/Is-there-any-way-to-copy-an-account-sub-hierarchy-td1424297.html

There is reference in that to creating an "Example Account hierarchy" by
hacking the XML -- is there any info out there on where or what exactly
you need to edit in the XML file? I'm comfortable with this type of
thing just would like some direction..