New squareback, some rust

[JReconco]

Hi there! I bought this 73 and a 71 parts car a few days ago, I checked the car for rust and this is the only cancerous rust that I found. I took pictures after I hit it with a hammer a few times to expose it.. What is this area? How do I get at it? From inside the car? Right above it on the body are those grill vents, they are packed with olive leaves and pine needles, how do I get that clear?

[LeslieTroyer]

That is a very common place for the fat chicks to rust -- the drain plugs fill with junk and plug, then the water sits there and rusts out.
Beyond that rust there is probably some rust on the "water tray" behind where you see the rust. You'll need to open that area up (cut or bend up from the rust line to the top back of the firewall. Clean the water tray and paint with a good rust inhibiting paint. -- Pay special attention that the joint at the water tray and firewall has all holes patched, so water doesn't drip down on your feet. I just pop rivitet a piece of sheet metal to close the area and then glassed over the whole thing. I know the repair will last only 5-6 years, but it was a car for a teenager, so it probably doesn't have that long to live. Otherwise cut back to good solid metal, and weld in a patch panel.

Les

[JReconco]

Thanks for the help!
So the only way to access that area is through that rust line? I am going to be removing the dash and the old AC tubing/wiring (some PO hacked the ac unit out) I was hoping to find access that way... It's surprising how poorly designed that area was. I just cant understand how those vents would ever get cleaned out if you cant access them..
I have a parts car that I am going to hack that piece out of, what kind of saw and blade would be best for this? Thanks JR

[LeslieTroyer]

I used an abrasive cut-off wheel (IIRC). I don't think you'll get much better access with the dash removed. Good luck.

LEs