After modifying my custom versions of vBulletin suite 4.2.3 PL1 I was wondering if it's at all possible to do an over-the-top install (upgrade 4.2.3 PL1 to 4.2.3 PL1) to get the latest updates to the master language and the like without having to completely rebuild all of my existing sites that are on older versions of my web apps thus saving me from having to manually deploy all the latest customizations to about 5 different sites (each running a different version of it's appropriate web app)?