My second 1965 Dodge Dart.

Time for windshield wiper seals. Also water can come in the bottom corners of the windshield. My best advice other than fixing the seals is to either have the car garaged during rain storms, or tarp it during rainstorms. Check your trunk spare tire well for water as well. Water gets past the old trunk seal as well.
The car I have outside, I just cover it with a nice tarp. Problem solved.

I have found the leak. Well, it is actually not a leak, lol, it is more something that is plugged up. It is the two slots in the cowl where the water is supposed to drain out. They were plugged, and it is full of gunk inside and other stuff that I have no proper name for. So, I am off to a hardware store to see if I can find a hose that is about an inch OD or slightly over and get into the holes where the rubber plugs are under the hood to clean it out. I have now flushed a little with water, and the water comes out where it is supposed to come out, and not down and out the vent doors under the dash. And I have a heater fan in the car trying to dry it up. Thankfully the rain in the morning went away and it is pretty nice here now, sun is out smiling at the car, and things looks better.

I wonder if it is something I can spray inside there to stop it from rusting, because I see it is some flaking going on. What is the name of that underbody stuff that never dries ?

Bill