will it work or does anything have to be changed to make it work

 

why would you want to put a head prone to cracking on?
IIRC, the 96 or 97 is supposed to be the best flowing head out of all of them. (not saying the intake manifold is though)

 

just found one cheap and i think mine is cracked so i just wanna put on a new one so I can sell it

 

It should bolt up and work just fine but, your 96 head is actually a better head. The newer 4.0 heads were made more smog friendly so they don't flow as freely as the older heads. That is why they put that new trick intake manifold on the 99 and newer XJ 4.0s get a little of the original HP and torque back.

 

unless you beat the living crap out of it I doubt it has a cracked head.. 99-01 were the only ones really prone to that. the 96 4.0 is pretty tough, its most likely just a gasket.
Why do you believe you have a head problem?

Pry "found it cheap" cause its pre-cracked for you. Guess you dont have to do the work for that one...

Also, i do not believe the 96 manifolds will bolt up.