Pontiac Repair: water leak in 95 Pontiac Grand Am GT, car leaks, windshild

Question
My son's car leaks water on the passenger side.NOT COOLANT. Someone said pull the cowl panel and look to see if there is a crack in the box on that side of the car.  There is a box without a top on it.  I reached my hand in there and felt the blower motor wheel. Two questions.
Does that box need a cover?  It looks like it to me, but not sure.
Where else could the water come from?
Lots of water was in it.

Answer
Hi John:

No that opening is the air inlety for the heater assembly. The cowl that covers that box has a seal on it that seals it to the windshiled and the body if the seal is damaged it will leak water. Alos when yoy take that cowl cover off take a looks at the body seam where the pillar post meets the body. The pillare is where the windshild is held in to and runs up to the roof. That seamat the body rusts out on these cars and will cause a leak as well. Good luck :)