2012-02-04, 10:21 PM
2012-02-04, 11:51 PM
There's no 'simple' way to do it, really. However, the wiki on updating your MyBB is fairly user-friendly and easy to follow. You can find it here: http://wiki.mybb.com/index.php/Upgrading
2012-02-05, 12:20 PM
You don't use a full install, you just use the full 1.6.5 package. Backup your database, upload the full 1.6.5 package so it overwrites your current files, run the upgrade script.