TM 9-2320-361-34 15-38. BORING CASE MAINTENANCE (Contd) b. Boring Gear and Case Removal I 1. 2. 3. 4. 5. Remove two screws (9), rack carrier nut (10), shims (11), thrust plate retainer (12), and thrust plates (13) and (14) from carrier (15). Record thickness of shims (11) and discard. Loosen two screws (20) and remove rack carrier nut (19), thrust plate retainer (18), and thrust plates (17) and (21) from carrier (15). Manually turn horizontal leveling worm gear (27) until boring case (16) is vertical (TM 9-2320-361-10). Remove nine screws (22), circular level (23), ten lockwashers (24), and boring case cover (25) from boring case (16). Discard lockwashers (24) NOTE Have drainage container ready to catch oil. Remove drainplug (26) from boring case (16). , 15-131