Rear Cab Water Leak

Hello. Did a search in both 2nd and 3rd gen forum as this issue is likely to occur on both models due to their similar design and wasn't able to find anything addressing this specific leak. See the below pic. Anyone ever have water leaking through here? What did you do to fix it? Thanks in advance.

 

I know the third brake light is known for leaking, I've never seen it from the molding, could it be the window seal?

 

Must be the window seal where it meets the molding. Issue occurs on both sides at the joint point between the molding and window seal. I had my lady pour some water from a cup on those two spots. The brake light is dry and tight as is the rest of the window seal, save for those two joints.