All of the 2WD out put shafts I have seen on a 4L80E , they are all bolt on style shafts.
The 4x4 shafts are different.
The E brake tail housing design of the 4L80E will require the whole tail housing , brake and yoke.. these parts are all application specific.
This brake assembly is quite large diameter and may not easily fit under the floor of most cars.
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