Logic Pro 9 Changing from LE9 to Logic Pro 9 - uninstall or not?


I'm about to upgrade to Logic Pro 9 and Mainstage 2 on an iMac with OSX 10.6. (Snow Leopard) from Logic Express 9.1.6. I've already got Logic 8 and an earlier version of LE9 still on the iMac (three versions in total). I'm looking for advice on how to uninstall these items whilst maintaining the projects I'm working on and keeping my settings, plug-ins and software instruments as they are. For example will the Logic Pro 9 installer automatically uninstall earlier versions and their support files?