I have a website which is based around the zen code base.
I have tried this but have been unable to complete it.
The possible files to change would be:
This is where the header files go for style sheets and js files:
/includes/templates/template_default/common/[url removed, login to view]
This is where the alt tags are:
/includes/functions/[url removed, login to view]
I will attach some screen shots and the code base in a zip file soon.