You should be able to pull the carrier, ring and pinion out of your old axle and pay a shop to set them up in the new axle. Plan on some $$$ ($300+?) though since you have to tear apart two axles and rebuild one. Probably closer to $150 to just set the new front up though if you do all the work yourself on the teardown. Then while it's apart you would be smart to buy new bearings and seals for the axle ($150+) from Randy's ring and pinion. I just kept shopping around until I found a 3.73 corp 10 bolt for my front end. Saved tons of money in the process. Check out my build thread and this link for more info on the swap...
http://67-72chevytrucks.com/vboard/s...d.php?t=240456