It's just that I have an opportunity to buy a complete rear with the gear I want (3.50), but it is open. I want a traction lock unit, and I'm trying to decide if it is worth the extra money to buy one that already has one installed.

The way I see it, I will eventually have to learn how to do it when I have to rebuild the trac. lok unit down the road, so I might as well learn now and save money.