TM 9-2320-361-34 3-18. ENGINE REPLACEMENT (Contd) I 10. Disconnect tachometer driveshaft (29) from tachometer drive unit (28). 11. Remove locknut (31), screw (27), clamp (30), and tachometer driveshaft (29) from bracket (32). Discard locknut (31). 12. Remove two locknuts (23), screws (26), four clamps (24), tachometer driveshaft. (29), and wiring harness (33) from two brackets (25). Discard locknuts (23). 3-59