I was trying to trace a small drip under my dash in my '86, but couldn't find it at first. Then I looked in the cowl, and there's a small rusty spot inside. Anyone ever seen this? I haven't. How do I get in there to weld? If not, can I block it off or will it cut off the air to my heater?

 

The truck is an antique, (30 y/o) wouldn't be surprised any where you find rust. As for fixing it? .... consult a body shop.
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