it's time to find my rear axle

I'll tell you what my dad use to say to me. "Never be afraid of buying the best, you'll never be disappointed." If you buy a Dana 60 you have the right rear end for what ever direction you take your car. I have used a Detroit locker in the past. Several times, never had a problem.
I also thought of the Ford 9 "model, with the ease of changing the ratios quite easily.