If you can find a hole, best to take out of car and place in a warm room to dry well. Then patch the hole, either a bit of araldite or something over the hole, araldited down to seal it up
With my E36 replacing the headlight gaskets did the trick, but if there is a quantity of water in there as well as moisture on glass then I would think something else is going on, like a crack/hole. It is worth a try though as the gaskets are cheap
