Help with Box Plot (Box and Whisker) - trying to overlay a marker on the chart

I didn't get any help in the chart forum - so I thought I'd post here in case anyone has any ideas...

I'm new to box plots. No problem creating a boxplot chart - but I want to overlay a single set of scores so that those scores are marked with an X or something (so someone could see where their score is in a cohort). I've tried to attach a mock xls which shows what I'm trying to do – BUT the attach icon isn’t working (I’ve tried both Chrome and Edge). So I’ve attached an image of the mock sheet instead.

snip_20170408120944.jpg

Really appreciate any help.

Thanks for the responses.

@AVK. Perhaps I wasn't clear. what I need is a single score to be marked against a box chart. i.e. if you were a student in a class - to show where your exam score was compared to everyone else that took the exam.
@mrShorty - Thanks that link looks helpful. I'll read through it and see if it helps me address the challenge