P38A Passenger side water leak

Hi all, I have a leak on the passenger side and have removed the pollen filter housing,which showed that there was water getting under the seal at the bottom ,I have removed and sealed this and replaced the housing. there is now no water in the filter housing. If I shine a torch I can see water in the bottom of the fan housing below .Has anyone had the same problem or any idea where the water is entering.Is it a big ob to remove the fan from inside of the car to get a better view. thanks for any help,I would appreciate it.

There is a small hole in the scuttle which should drain off water. if this gets blocked you can get puddles which leak through the pollen filter...

Thanks,I will have a look