Well, I've talked to a lot of people, condisdered the cost on several options and have determined that finding a 4.0L is the way to go. Plenty of power and torque for California Wheel'n, easy to swap (I've been told the tranny bolt patterns are the same on the 4.0L and 4.2L.) and fuel injected.
It's amazing how much money you could dump into a 258. An engine rebuild with the Mopar MPI kit would cost around $4000. The 4.0L engine swap is the only option that really makes sense. A V8 swap might be cheep as well, but in spite of how often its been done it still seems like there would be way to many hidden surprises to over come.