i found water in the boot so i tested for boot lid leaking there was none, put water around rear window and ran the side of the car, and i found water in the boot again. then i tried again and used food colouring around window gently and not letting it over flow so it went around the seal and the colour used didn't show in boot. So i used a different colour around the metal bit the at covers the metal between the quarter window bottom and the roof between rear windows. Then i opened the boot and found the water with food colouring so i removed the little metal cover and silicone it back on and now it doesn't leak.