Since the topic of alignment is being discussed, I would refrain from using the Fender Bracket to define the hole location.
Instead, there should be enough of the remaining areas to locate the centerline of the holes. Next, using a flexible steel ruler, scribe a line approximately 4"-5" above and below the centerline of the two holes. Do the same scribe 90° (-perpendicular) on the holes extending 3"-4" past the holes. When you cut to remove the damaged metal, the scribes will be on the fender still which will allow you to locate exactly the ℄.
Make sure when you cut the damaged metal that you cut smaller than the patch panel. This allows you to scribe to opening size and then cut, trim & file to have an exacting fit that can be fuse-welded and planished.