I just had this done a week ago. I gave the parts (repair kit and new stay) to my mechanic (dealer experience for 25+ years and more) and he started to work on it. It turned out that the metal was really bad (kind of obvious but I was hoping), and he ended up having to weld inside the door. You cannot see it after the work is done.
He did mention that it was difficult to work and weld and removing the door skin would have been a better option. Since the door is perfect otherwise, I am glad he was able to finish it going from the inside.
Good luck.
