Customization on Debian

What’s the best approach to keeping a debian installation of RT
under CVS to help manage local changes and customization?

I’m thinking of either installing the debian package, then
doing a cvs import of


or installing from the current rt source (tar.gz) download and
then cvs importing the directories where RT gets installed (those
containing html, lib, configuration, etc.) similar to above.
Is there any significant advantage to one approach over the other?