I have four of those brackets that mount on the top hinge of the doors. There are two holes in the hinge and two holes in the swing arms that hold the restricting (door hold open springs) brackets or arms in place. I think you have to remove the hinge pin in order to install the arms. I found holes in each top hinge to mount the springs but don't know anything about the need to weld them. Are we talking about the same parts?

Here is a picture of the door hold open springs that I have: http://www.americanclassic.com/images/dp238.gif