Change Thumbnail Position in WordPress

// Changing featured image placement in custom post type

add_action('do_meta_boxes', 'customposttype_image_box');

function customposttype_image_box() {



 remove_meta_box( 'postimagediv', 'customposttype', 'side' );



 add_meta_box('postimagediv', __('Custom Image'), 'post_thumbnail_meta_box', 'partner', 'normal', 'high');




}