properly an operator may wait until the truck 30 and trailers 32 34 are driven off the unloading station 12 this may be safer inasmuch as the doors 36 are typically positioned at the edge of the unloading station 12 over a large drop to a hopper pit pile conveyor belt or the like meanwhile unloaded the trailers 32 34 can move even with doors 36 unlocked a withdrawing step 592 may include deactivating the lifting mechanism is supporting the floor 246 of the trailers 32 34 for example one may deactivate the hydraulic cylinder 528 and piston 530 allowing the belly support 60 to drop slide pull or fall away from the longitudinal support member 254 a a withdrawing step 592 may include having an operator verify that the belly support 60 is positioned flush with the bearing surface 50 a releasing step 594 may include deactivating the tensioning system 114 of the anchors 62 in some embodiments lifting and locking the door 36 may take place after the tensioning system 114 is deactivated the releasing step 594 may also include removing the fasteners 110 from the anchor receptacles 274 in some embodiments the releasing step 594 may include hanging the fastener 110 on the cable 100 extending along the unloading station 12 or otherwise stowing the fasteners 110 and lines 112 an operator may also release the tension in the comealong 230 and stow the comealong 230 in.