Will I be able to use the same installed 1.0.5 ptr that was released before for when the new 1.0.7 ptr comes out or will I have to get a new one. I never uninstalled it because I tought it was a base client that all future updates would be on so its just sitting on my computer taking up space. If I will need a new one for 1.0.7i would appreciate knowing so I can uninstall the old one and free up some computer space.
You will have to update to the new content when the client is released. I think you can keep the current though, and just apply the patch. It worked that way in WoW anyway.