X-stage assembly question

I have a small potential problem - when I took down my stage I think I must have loosened too much or too many screws, as when everything was disassembled I was left with a bolt laying on the ground. Does anyone happen to have a diagram of the section where the pole meets the stage, or know where that bolt might have come from so I can put it back??!! It's the model before the current one, I got it last year.