Rain entering cabin

[Walshie]

I have posted about this problem before but haven't been able to sort the problem.
To recap, I have rain water entering the passenger footwell at the front of the car ( right hand drive) I have poured water down the front drains and this runs out ok, I have put an air line down them to make sure they are not blocked, I have replaced the missing rubber grommets to the drain holes. I have had the door membrane replaced even though the door card was dry, I have re sealed the cabin filter casing and have now run out of ideas.
Is there anything I am missing.
The water is entering from behind the dash but not through the screen, it runs down the bulkhead and onto the carpet. The carpet under the seats always remains dry so it isn't the rear drains.
Fed up and at the moment defeated.

HELP