Nissan: Nissan Terrano, nissan terrano 2, blue masking tape

Question
I have a Nissan Terrano 2, M reg. I have water coming in from passenger foot well, I have already checked sunroof drain holes and these are clear. I have looked under bonnet and can't see anything out of place. Could it be coming from the grill in front of the windscreen? Or is there a drain hole somewhere that could be blocked?

Answer
This one could be a pain in the ass. Find a garden hose and let water run over the vehicle while you are inside with a flashlight looking for the leak. You may have to remove some minor panels or lower dash covers. There is no easy way. Often times I have used that blue masking tape to cover areas to try and track down leaks. Was this car ever crashed? Has it had any modifications?