TM 10-3930-659-20 15-1. ON-BOARD CRANE MAINTENANCE (Con't). b. DISASSEMBLY 1. Remove cotter pin (9), pin (12), two spacers (10), and front groove pulley (11) from boom (6).  Discard cotter pin. 2. Remove spring lockpin (8) and pin (17) from boom (6) and mast (16). 3. Remove cotter pin (7), pin (5), and rear groove pulley (18) from boom (6).  Discard cotter pin. 4. Remove spring lockpin (13), pin (15), and shaft collar (14) from mast (16). TA706762 15-4