1972 XR7 convertible cowl area question

I am in the process of restoring my 72 to get it ack on the road. In the process I am trying to remove rusty areas ( so far drivers’ side floor pan and battery tray) When I removed the front fender to get to the inside fender area, this is what I saw. I imagine that there should be some type of opening to allow the cowl area to drain. My question is how much metal is actually missing? Best way to repair? Any input is greatly appreciated!

OK, apparently I also need help in posting pictures. I have three photos which show the area, but can’t figure out how to post. Thanks

You can use the upload arrow which will let you navigate to the picture location on your device, or you can simply drag the photos into your post.