I'll keep this short, feel free to ask clarifying questions. On my 1967 Barracuda hard top, it has dirt and debris inside the cowling grates that are right under the windshield. I see some, what I guess are drain holes on both sides (passenger and driver side) when you open the hood. I can also see and feel a bunch of dirt in it. It is causing water to leak on the inside of the car. I don't see any convenient ways to cleaning this out. The grates are super close together, so getting an air hose down in there looks almost impossible. The holes on the side are also super difficult to access.

Anyone have issues with this before, and know of a fix? Can you get at it from inside, under the dash? Thanks.

 

Blowing it with air, poking at it with a cote hanger and then blowing it some more and finally useing water to rinse as needed. If water comes in more than likely you have rust in the cowl.

 

You can gain access from under the passenger side dash where the fresh air intake (or cable vent) is. Not an easy task but all of the foam seals need to be replaced anyway. Here is a photo of a firewall showing the hole. Once cleaned you can tape off the top cowl grill and the circular hole under the dash then spray rust converting paint along with compressed air in the end drains. This will coat the entire inside of the cowl.