Having done (or almost finished) both the 5th Ave clip and a Dakota clip, the Dakota wins hands down.

You will need to cut the frame off your car to do either, the 5th Ave was last produced in 89 and there is very little support for that suspension. A Dakota was first produced in 87 and is still in production (though I'm don't know if any of the componets on the new trucks fit the older chassis). Do you want old tech or more modern tech, and think about what parts availability will be in 10 years. Gene