take a look at a chassis book such as the green book p.274. It should show the screen and the cup it fits into, as well as the wire retainer for the screen to the cup and the arm for the pick-up. The screen should not be moving 1" side to side unless something is loose such as the arm holding the pick up to the pump. If that is the case your oil pressure will be very low. If the screen is moving up and down 1" it is possible the wire retainer has come off and allowed the screen to drop. If so check your oil pressure with a oil gauge screwed into the block and see if your developing proper oil pressures, if so let it go. If not drop the pan. make sure just the screen is moving and not the cup it fits into.