If you have a computer with excel, there is a great tool that will give you some great placement numbers based on the length of rod, number of eyes you plan to use, and placement of your stripper eye.

I use this tool as a starting point and honestly, I've never had to change the location of an eye after a deflection test. I believe I reference it in one of the sticky notes above. If not, let me know and I'll get it to you. It is free of course.