I'm just passing on someone elses opinion here:
Parts Mike advises not to use a Lock Right or simular locker in the rear of a vehicle that sees a lot of street time. The constant lock and unlock of the mechanism will wear it out relatively quickly. A stronger case type locker would be better, such as a Detroit Locker. An ARB would be even better for your uses. It's a matter of how much you are prepared to spend. I would also do something about your two piece axles if your going to use a locker. A one piece kit would be the best case scenerio, torquing the axle nut down to 400 ft.lbs sounds like a decent idea if money is an issue. Another one is to have an extra keyway cut in the shaft.
jo-jo
'77 CJ5 Fozzy Locker
20 degree RTI 1250