Got caught in rainstorm at a car show and when cleaning up the car after, I happened to check the drainage holes on the driver and passenger doors on my 68 GTO. To my surprise, I found both doors had rubber plugs in the drain holes which are obviously factory made. I carefully removed them and found a considerable amount of water was trapped inside the doors due to the plugs being in place. I had not been aware of these plugs and thought it might be of value to others to check their cars. Anybody know why the plugs are present? Maybe meant to keep dirt and debris from getting inside the door and supposed to be removed when washing the car? No need to be carrying any water inside your door, right??