BE KQ specific, and the carrier is machined for larger thrust washers/spider gears.
Springs are wound in the opposite direction of the green 12 bolt spring. Side gears are 16 teeth vs 18 standard 12 bolt and are thicker than the 18 tooth. BE spider gears are larger and still have 10 teeth like the smaller 10 tooth standard 12 bolt.
There are some comparison photos in some book I looked at once.
I had posted on this before and can not find it..
Mike