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Nissan 240SX Performance Modification/Differential/How to weld your stock diff
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
Weld side gears to spider gears and/or to case.
Welding the gears should involve 8 small welds with plenty of redundancy and it is removable.
Welding side gears to case and removing spiders produces a simple spool but requires a good weld.
Welding everything will give the most redundancy and strength for extreme use.