I unscrew everything from the playfield until it is all sitting loose but still in place. Then I slide a piece of stiff cardboard or thin ply over the playfield underside, keeping the harness and mechs in their approximate place. As you slide you'll encounter things you missed and undo, then keep on going until you have the lot on the cardboard, them slide the lot off and put somewhere where the wife/kids/pets won't disturb it, ready for the reverse action when you're done.
