TM 9-2320-361-10 2-32. OPERATION OF EARTH BORING AND POLESETTING MAINTENANCE TRUCKS (Contd) (12) Check bored hole depth through sighting holes (2), (3), and (4) in derrick tube (5). (a) If bar guide (1) is sighted through hole (2), bored hole is 8 feet deep. (b) If bar guide (1) is sighted through hole (3), bored hole is 9 feet deep. (c) If bar guide (1) is sighted through hole (4), bored hole is 10 feet deep. (13) After boring, push feed control lever (7) forward and pull drive control lever (6) back (position 5, table 2-4) to raise auger (8) without pressing bumper spring (9). (14) Pull back on control levers (6) and (7) (position 7, table 2-4) and lock in position. Set hand throttle (11) at engine idle speed, raise outrigger legs (10) (refer to b. of this para.) and move truck away from hole. 2-172