4.2 swap to a 4.0 Please Read And Help Me

[aj279606]

I have a 1988 yj with a 4.2 carb motor and I have no cylinder pressure and i really dont have the money to rebuild the engine, so i was thinking about buying my friends 1987 yj 4.0 carb motor but the transmission is broken. What my question is will the 4.0 go into my jeep with my transmission or will i have to fix his?? and will the 4.0 have to modified in anyway to bolt up in my jeep? and do i need to use his computer and wire harness too?? :???: please write me back a.s.a.p. or email me at aj279606 at hotmail dot com