But the diffs rotate in the same direction on a 4wd, implying that actually the orientation of the screw verses rotation direction makes no difference.
They only alter sides on the 4wd as the orientation of the entire diff flips end to end to ensure the wheels go the right way. Get it wrong (as you can in a 1.8th or Rango) and you get a 'push-me pull-you'!
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