These vehicles are constructed with a unibody frame and as such have no frame. And yes the front axle can be interchanged. If your 96 has damage extensive enough to warrant a total front end replacement and the frame itself is bent then I would suggest that its probably totalled beyond repair and that you have two junk vehicles there.
The front axle did not have limited slip from the factory.
No.
No.
No.
Change them. They are not serviceable.
Yes. The body style of the ZJ from 1993 - 1998 are the same.
Look for a driveshaft going to the front.
It is just above the front dome lamps.
Cut it out and weld in new steel.
Bad Struts
It is under the front of the passenger side cylinder head.
I would not recommend it, unless this is going to be an off-road only Jeep. There is just too much that can go wrong.