hacked out dashboard widgets, cant get them back?

hi, im customizing wordpress for better display for other users, and im removing some menu items by css, and i was using this code to remove dashboard widgets:

unset($wp_meta_boxes['dashboard']['normal']['core']['dashboard_right_now']);
unset($wp_meta_boxes['dashboard']['normal']['core']['dashboard_recent_comments']);
unset($wp_meta_boxes['dashboard']['normal']['core']['dashboard_incoming_links']);
unset($wp_meta_boxes['dashboard']['normal']['core']['dashboard_plugins']);
unset($wp_meta_boxes['dashboard']['side']['core']['dashboard_quick_press']);
unset($wp_meta_boxes['dashboard']['side']['core']['dashboard_recent_drafts']);
unset($wp_meta_boxes['dashboard']['side']['core']['dashboard_primary']);
unset($wp_meta_boxes['dashboard']['side']['core']['dashboard_secondary']);

i saw that i should use remove_meta_box instead, but right now im stuck where even if i have none of this in my fuctions.php file, i still dont get the Primary, Secondary [wordpress blog / news] and the Right Now widget!

i dug some more and wp-admin/includes/template.php says

// If a core box was previously added or removed by a plugin, don't add.
     if ( 'core' == $priority ) {
     // If core box previously deleted, don't add
          if ( false === $wp_meta_boxes[$page][$a_context][$a_priority][$id] )
           return; .....

right now what im trying is just to get them back but they dont even appear in the screen options.

i only made modifications in functions.php, but i dont know what more arguments i should put in set($wp_meta_boxes[.......?? to fix this, or even if it would..
please tip me in the right direction.
Thank you so much.

adir