JPI 830 RPM Issue

[CL605]

I have a 1977 J with the dual mag setup, and I know the JPI 830 needs to be set up as an 8 cylinder engine in order to display the correct RPM. I have read everything I can find on how to do this, and I have gotten as far as the setup display that asks "7,8,9 cyl" followed by a Y or N. I cannot find how to select 8 cyl. JPI is closed for the holiday and I am getting the annual signed off tomorrow and would like to fly if possible. Anyone remember how to program 8 cylinders into the 830? Keep it simple, I'm not that smart.