Diff question

If the pinion bearings are still good, there's no need for any fancy tools and/or shims to set things up. A simple dial indicator to set the backlash is simple and all you need. If the pinion bearings are bad, yeah, you need to do the full monty. If you don't want or need the sure grip unit, you can probably trade it for a complete open 3rd member with the gears you want from somebody here.