In the event something goes terribly wrong (which it won't if you use the installer) just boot to the recovery console and straighten out the mess. If you're really worried about it, set up a user account and call it LiteStep (for example) and set LS as the shell for the current user only. Then if you ever need to get into explorer, just log into the old account. I do that all the time. It makes life easier when working on visual styles, etc.