[CentOS] logwatch customization question

Sun Apr 9 12:36:17 UTC 2017
Robert Moskowitz <rgm at htt-consult.com>

Logwatch is installed, and I am assuming by how empty /etc/logwatch is 
that it is running from defaults, which I find in 
/usr/share/logwatch/default.conf/services

I want to customize ONE service.  dovecot.

Do I copy /usr/share/logwatch/default.conf/services/dovecot.conf

to

/etc/logwatch/conf/services

and edit it there,

or do I have to copy ALL default.conf/services/* there and modify 
/etc/logwatch/conf/logwatch.conf to look there?

The README is rather not helpful on this.

How do I modify ONE service (and not just make the changes in 
default.conf that I have seen in a couple howtos.

thanks