either way you go Id run lockout hubs as it will help when you go to turn on the road plus keep your front end from rotating. setting up gears is really fairly easy. youll need to remove the front axles to do it and its a perfect time to check everything out and replace any seals, brakes, ujoints,ect. a locker is good for mostly offroad use and a limited slit is more friendly on the street but not as good offroad as a locking diff. either way, youll be impressed in off camber situations with 2 wheels on the ground.
67 M725, 67 M715, 68 M715