How to add a normal distribution to a histogram

[AdamCPTD]

Trying to add a Gaussian (Normal Distribution) curve to a histogram using a
scatter chart over top of a bar chart.
The problem I have is that the scale of the histogram doesn't match the
scale of the Normal Curve. I could set them equal manually, but that is
impractical because the scale of the histogram is always changing as new data
points are added.
Can I plot the Normal Distribution on the same X axis as the histogram, or
can I have the scales of the two series match somehow?

Thanks,

Adam