My bow came new from the factory and I was told the top pin is 10 yds, middle 20 and bottom 30. The middle is dead on at 10 but the top nad bottom seem to be way off. How would I go about getting the top to 10, middle 20 and bottom 30. Common sense tells me to adjust my top pin so it is in line with the middle and go from there. I am completely new to this so any advise would help. Thanks