My 2004 Rubicon leaks due to a worn out bottom seal on the rear liftgate. The dealer wanted more than $200 for a piece of plastic and rubber, so I ordered that part online. But, it didn't come with any instructions. Anyone have any tips on installing a new assembly. The old one seems like it's glued on, but I can't see inside. So, I don't really know what I'm working with. Thanks for any help.