Well, this isn't the easiest of repairs. I think I have some pictures here but the fender is double layered up there, welded, and filled with inches of rock solid seam sealer and dirt, mud, etc.
This is what I stared with, not a pretty site. I looked around but found other donor cars were just as bad, but the time to take a piece from another is just as bad as fabricating.
I cleaned thing up and cut out the rust back as far as I needed to get to strong metal.
I tried making templates out of cardboard and plastic but It didn't have the properties I needed. I ended up getting the thinnest sheet steel I could find, I believe it is 24 Guage, and I was able to work that and modify it to my satisfaction. Once I had a templace I thought was acceptable, I duplicated in 18 guage.
Now I have a rough fix. I still need to work from under the fender to seal things up and also to adjust the door gap, but there were a lot of little parts that needed to be welded to make the whole.
Good luck, take you time, it can be done, but it will take time...