If you've done ball joints before, there's no surprises. The upper joint uses a castle nut looking thing (that needs a special socket) that threads into the axle housing and adjusts the ?caster?, anyway you could theoretically just leave the nut (the stud will just come right out of it while the nut is still in place) and replace just the ball joint. Manual hubs rock, I put 'em on and they work fine. Also while you're in there that deep, just replace all seals and bearings. It's totally worth it. You'll kick yourself later if you don't.
It'll look something like this about the time you start getting tired:
Oh, see the 24 oz. hammer under the drop light? You'll use a lot of that.
Good luck,
Mike