just the rear end? its easy as hell..
if you have a 7 1/4 rear then just go find a large bolt pattern one and install it.
can go abody 8 1/4 rear. thats large bolt pattern already and is bolt in. driveshaft may have to be modified.
if ya have a 8 3/4 rear then just change the axles and find big car brakes and bolt it together...