I replaced the old hydraulic pump on my 10 wheeler grain truck with a new Muncie pump. It has two pto stub shafts and I'm not sure which one to use. The directions show nothing and there's no casting arrows on the pump. The truck pto turns CCW if facing the shaft, so the pump needs to turn CW. The pump shafts sit one on top of the other. The old pump used the top shaft but it is over 40 years old and was told it was obsolete.