With the case closed, place the Unibody top-side down on a flat surface. Depress the grooved side of the access door release latch enough to grab the free end. Lift the release latch until it is vertical. /Guide/Installing-MacBook-Unibody-Model-A1278-Lower-Case/756/all#s4172 The access door should now be raised enough to lift it up and out of the Unibody. /Guide/Installing-MacBook-Unibody-Model-A1278-Lower-Case/756/all#s4348 Be sure the access door release latch is vertical before proceeding. Grab the white plastic tab and pull the battery up and out of the Unibody. /Guide/Installing-MacBook-Unibody-Model-A1278-Lower-Case/756/all#s4122 Remove the following eight screws securing the lower case to the chassis: One 3 mm Phillips screw. Three 13.5 mm Phillips screws. Four 3.5 mm Phillips screws. /Guide/Installing-MacBook-Unibody-Model-A1278-Lower-Case/756/all#s4127 Using both hands, lift and remove the lower case off the upper case. /Guide/Installing-MacBook-Unibody-Model-A1278-Lower-Case/756/all#s4128