Um ... it's been some time and I never "perfected" the hack. :)

Have a look here https://github.com/LanX/Macro/tree/master/lib

Macro.pod.tpl has a template (read hack)

podbuilder.pl reads the template and Macro.pm and creates Macro.pod and README.pod

update

As you see it's a primitive pod parser which grabs some parts between =head directives till =cut.

you could just filter out any underscored _private headline or use a =head1 Internal to mark them.

(not sure why it's missing in the git-hub version)