I’m a big big fan of CMB2

Is there a way to add custom meta boxes to existing page editor boxes, ie “Page Attributes”, “Featured Image”, “Publish”, etc etc etc. I want to add a meta box for positioning the featured image. Naturally it makes sense to add option to the “Featured Image” box, but I can’t seem to locate documentation on adding such a field to something in WP that already exists in the editor.

Any suggestions?

The page I need help with: [log in to see the link]