Change the edit page for a custom post type?

As far as I know you can remove almost everything except the title h2 tag, and the .postbox-container border. Also note that the #message is not visible by default but can pop up depending on what you do.

When you register your CPT set supports to an empty array.

'supports' => array ('')

Then you can use the following to unset the publish and slug (the slug in not visible by default but it is there under screen options),

function remove_metaboxes(){
    remove_meta_box('slugdiv', 'obpcontacts', 'normal'); // Slug
    remove_meta_box('submitdiv', 'obpcontacts', 'side'); // Publish box
}
add_action( 'add_meta_boxes', 'remove_metaboxes', 11 );

You will be left with a few elements that might need to be removed with javascript:

//jQuery enqueue only on your CPT
.removeClass("wrap");  //remove all CSS