you'll need to regear the D44 to match the rear; you will have a hard time finding one w/ 4.88s installed already.

you'll need a new rear leaf pack; AAL isn't gonna' do it.

plan on rebuilding the front axle, unless you get one in mint condition. You don't want the whole thing to come together, only to find out after it's all on the truck, that the ball joints are bad, or the gears are chipped, or the axles are worn out, or the hubs are bombed, etc. You can rebuild an axle for relatively cheap; and if you plan ahead of time that you're going to do that, anyways, then you don't have to pay as much for an axle to begin with.

Locker for the D44. Or just weld it. Doesn't matter which. But lock it while you've got its guts splayed out in front of you.