1983 - Water Leak into cab - Windshield, or Cowl

[83Ram50TDinPA]

Has anyone have any experience with removing the cowl on a 1983 ? Once the rain stops and it dries out, and am going to test each item by dumping water down the cowl... if think you see where I'm going with this. Once I find out where the leak is, probably the cowl, I cannot see how it's removed to clean that area out, and fix the holes. There are no bolts, and it seems to be glued in on each side.

[85Ram50]

AHA! There are two access panels from inside the truck. You have to remove the ducting for the heater and a bunch of the dash. You can see pictures in my "bench seat" thread. There was a mouse nest behind one and it rusted through there on mine. You can stick a vacuum in there and you can squirt rust converter too. IDK that there is a way to remove the cowl without drilling out the rivets or breaking welds.
Edit- Post #18 http://www.mightyram50.net/vbulletin/showthread.php/7811-bench-seat You see the driver side is rusted and the passenger side it clean.
Edit2- The inside access panels are on either end where the cowl starts to flow down the inside of the fender panel. I don't have the access on the passenger side in the firewall. There is heat shielding there on mine.

[tortron]

Cowl is welded in on 1st gens
Access via removing the wiper motor and the identical panel on the other side of the firewall in the engine bay.
They drain out behind the guards.
Lesser access via the heater air intake in the middle of the dash or the vent air duct on either side. These have a rubber foam gasket under them which may be where your leak is

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There's a lip around the heater intake in the cowl. Designed to stop water running down into it. It's a prime spot for leaves to gather between it and the firewall and rust through. If that's the case there's probably some bubbles forming on the firewall as well, you have to cut it out and fix inside then weld it back.
Basically every red spot on my photos is where your truck is likely to rust