Water leak- wet RR floor. How do you remove the quarter seam cover?

[69marquis conv]

I have a leak somewhere in my '06 GM that is allowing water to puddle in the right rear floor. After removing the seat and rear carpet from the floor I had a friend spray the car from outside while I was inside looking for the water entry point. It appears that the water is coming in through a hole from the hollow part of the quarter, just behind the door opening. See pictures. I think I need to remove the quarter panel seam cover and look for an opening in the seam sealer. Does anyone know how to remove the cover?
I have attached pictures of the hole the water is coming in from.

[Spectragod]

You take the "C" pillar trim off, 2 or 3 10mm nuts IIRC.

[Marauderjack]

Mine leaked into the trunk on the right side and it ended up being the rear window not being completely sealed down the side!!!:argue::mad2:

I managed to run the snout of a tube of silicone under the rubber trim and get it sealed but it would be better to remove the rubber trim and do it right!!:beer:

Good Luck!!