An operator manually pushes the carcass down the rail to the scale location. The trolley rolls onto the live rail, then settles in its’ “dipped center.” This slight indentation in the rail settles the trolley into position allowing the operator to be assured of proper positioning. The operator will then reference the digital weight indicator that is interfaced to the monorail scale, entering the appropriate tare to determine the net carcass, or primal, weight ensuring a highly accurate single trolley weighment.