ford mazda

Can somebody help me? my b2500 posi differential has a weird movement. I've been told to change the differential. but mine is LSD and if I buy one at a junk yard most likely it wont be LSD. what other type of differential can I adapt to my truck? a mustang's? explorer?

So after hitting a deer at 110mph my front end was a tad bit screwed. Frame was sprung and driver side tire was pushed back an inch and negative camber of a inch, I got that fixed at a good frame shop in my town. The only last is my header panel and grill, instead of spending alot of $$$ on...