I know that you don't weld to the carrier... I just wanted to see if people removed it or not, I ask about the heating cause Some old wheeling guy I met the other day was telling me to preheat it in an oven, it will open the gears up slightly, weld it up, and then let it cool in an over that is turned off, so that it cools very slowly.
I welded up the spyder gears in my old YJ, but that was 6 years ago. I welded them up inside the carrier, never really had a problem, but it got totalled after only 2000K miles after I locked it so I am unsure if my method was indeed long lasting..