Water from leak n.s boot vent panel

[Edhertz]

Hi folks,
I am writing to ask if anyone has been here before. I have just stripped out the boot liner and felt because the felt is soaking wet.Traced it to two causes. One (worse) turns out to be coming from the o.s light cluster the other is from the vent panel on the n.s of the boot. I've sorted the light cluster seal and is now fine but I'm having having difficulty tracing the source of the leak on the n.s. Sun roof drains are clear and checked the push on connection on the sunroof frame, drizabone, also the roof rack holes are sealed up. I have read the threads about boot leaks,carpets and their probable causes but could have missed one on boot vent panels,
My thanks in advance.