TM 9-2320-209-10-1 (2) Rigging to swing open at top for regular loading or unloading. FRAME 1 1. Move chains (1) up, from locking position at bottom of lower locking slot (2) to hole at top of slot. Take chains out of slots and retainers (3). 2. Put chains (1) through holes at top of upper locking slots (4). 3. Pull locking pins (5) out and move tailgate (6) down slowly. Do not let it drop. 4. Pull chains (1) through until they hold weight of tailgate (6) in open position, in line with truck bed (7). 5. Slip chains (1) to bottom of locking slots (4) to lock them in position. 4-237