Rear End Side Play

With all 4 wheels on the ground and the 4-speed out of gear if I try to rotate the driveshaft (yoke) side to side how much play (movment) is normal?

If your talking side play of the rear pinion yoke? No play should be felt or scene. If you do have play, check the pinion nut to see if it is tight, if so then it's time to rebuild the third member.