2.5” x 4 and 2.5” x 6: from the top of the bracket, using a screwdriver press each hook down to release the clock. Then pull out to unsnap bottom hinges.
4” x 4 and 4” x 6: from the top of the bracket, insert a thin screwdriver into each notch and gently move the screwdriver sideways to unlock the clock. Then pull clock forward and up to unsnap. Lift out.