I hate to mention this, but just because you can see where the leak exits, does not mean that's where it's coming in.
Case in point was a Rover 45, leak was dripping out of an aperture (clip hole from memory) half way down the drivers screen pillar. But the water was actually getting in through a split in the seam sealer above the B-pillar, then tracking forward inside the body structure.
To make matters worse, the split was so slight, it took a few minutes of water testing in the right area before anything appeared.....so easily missed.
Took me a good few weeks with the interior stripped & water testing to cure all the leaks on that one. But I'm pleased to say been bone dry since
