Hello all, I know this has been discussed in the forums, and after reading the posts I got the tool box out and attacked my Lag.
I decided that there wasn't any stains in the headlining and intial inspection showed no water ingress through the doors and seals, so was my leak coming via the Pollen filter box/housing, before dismantling the dash board to see if it was I thought I'd prefer looking in the Scuttle tray first. This was the answer as you will see in the following pictures detailing how remove bits, find clear and clean these little butt aches!
I decided to start with the passenger side which IS the easier side
Remove the seal,
which is also very easy to replace, then remove the 2 little plastic lugs with a quarter to half turn then gently prise these out (as shown in pic from drivers side)
to remove the scuttle cover look where the drivers and passenger side covers meet in the middle,
lift the drivers side and slide the passenger side cover from underneath it,
now holding the bonnet up while it is not connected to the stay
will allow you to move it accordingly to enable wiggling of the scuttle cover to remove it from under the edge of the bonnet towards the front of the car, you will then be able to see into the corner of the skuttle,
you will find a rubber flap that in my case was stuck shut with goo stuff!
prod it with your finger or screw driver
and watch the water run away!
Use something like a plastic bottle of some sort
and power flush the residues out through the drain. the pics that follow will show where the opening is that goes through to the pollen filter and where my finger points is where the water was sloshing into the filter housing and into my passenger footwell when turning corners,
When you have done this I advise clearing and cleaning the nooks and crannies (gullies) near the bonnet hinges and where the rubber was removed,
Once the cleanings been completed you can put everything back as you removed it..
Now the more difficult drivers side, would need you to remove the wipers, which is quite simple BUT, you can just prise the Scuttle cover enough
to slip a small hand in to do the dirty work
A thorough flush through squeezing your water bottle into the gulley should blast residues away, check before reassembling.
I hope this helps with most water problems in the foot wells so good luck with the DIY