The axles aint welded together. Just the spider/side gears in center of carrier. Remove axles, Remove spider gears and replace with one of the small lockers like powertracx lock rite, install axles Or remove carrier, remove ring gear off carrier. Buy a full carrier locker like the detroit locker, set ring gear back up on it, set contact patterns, back lash and all of that as your installing new carrier, install axles
Just change out the differential for the locker. The axles aren't welded to make a Lincoln locker, just the side gears in the differential. The locker would replace the welded parts anyway. You should have a shop set up the gears, though, as getting it wrong can cause premature wear or failure of the ring gear and pinion gear.
