Once you put the oil return line on make sure to fill it with oil. Then spin it over by hand a few times before you start the truck. Once you start the truck let it idle for about 10minutes or so before the first drive to make sure the new turbo is good and lubricated before it's first test. After the test drive check all the connections to make sure they are good and tight.
Oh and don't forget you may have to clock the turbo to get it to fit just right on the truck.
Good Luck
DB