Occasionally, when you are really stuck, you start over again from square one and when you solve the problem, you feel really, really good.
Here’s the solution:
<?php $querystr = “
SELECT * FROM $wpdb->posts as wpost
INNER JOIN $wpdb->postmeta
ON (wpost.ID = $wpdb->postmeta.post_id)
AND $wpdb->postmeta.meta_key = ‘CustomField’
ORDER BY $wpdb->postmeta.meta_value DESC
LIMIT 5
“;
$pageposts = $wpdb->get_results($querystr, OBJECT); ?>