Vince,
Good luck with your project. I've never attempted something so ambitious but I have welded up a hook on a Husky hammer gun to put it back on face. I used a local micro welder to put just a little material on the hook surface without affecting the hardness on the rest of the hook. I instructed him to add material uniformly until the gun would just not close. I then used a ceramic sharpening rod and smoke to final fit. I got lucky; it only took about 15 minutes.
Good luck and have fun!
Phil