Water leaking into my cab, need help! Western Star 4900

The truck is an 07 western star 4900 daycab and the water pours in the cab every time it rains! At first I thought it was coming in at the hvac air inlet so I plugged that off but it's coming from somewhere above the hvac box on the passenger side and above the clutch pedal on the drivers side. It's a constant drip when it's raining hard! I had a beach towel on each side over the weekend and they were completely soaked after it rained! I have silicone everything on the firewall I could find as well as the roof, although I don't get any drips from the roof. I'm out of Ideas..

 

It seems to leak in behind the dash somewhere because it runs down the firewall, I'm thinking it may be the seal around the windshield because I see some water along the bottom of the windshield, no runs or drips from up above

 

That's kind of what it seems like. What did they do to fix them?