1/2 to 3/4 rear (14 bolt) is a direct bolt in, minus the u-joint difference, poss driveshaft length change, E-brake cable mod...but other than that is cake.
The front if converting to 8 lug....but still 1/2 ton is easy and fairly cheap. Goning to a DANA60 front is fairly easy too, but not easy on the wallet!!! /forums/images/icons/frown.gif /forums/images/icons/wink.gif