The hash mark is only good on the pump that engine left Brookville Road with (the plant where most of the 6.9 IDI’s through the 6.4 PSD’s were built is about 10 miles from me here Indianapolis, I drive by it every day) and if the pump hasn’t been rebuilt. Any time a pump is rebuild it changes the timing inside the pump. we had a member that had their factory pump rebuilt. They put it back on and lined the marks up. He found the timing was incorrect, just as expected. When the pump gets rebuilt, the timing falls wherever the replacement parts put it. This is why it has to be dynamically timed after install. That’s how the factory mark was determined. IH ran and timed the engine, then made the mark.