I wasn't able to access the AreaModel previously because I was referencing the wrong version. I switched to 2015 Q3, and I can access the AreaModel and get the PlotArea's LayoutSlot, BUT it's not quite what I need. I need to get the area inside the axes, that corresponds to the actual plotting space of the chart, so I can calculate where on the screen a data point is, and where a data point should be for a screen coordinate. Looking at the children of the AreaModel, there appears to be a Grid property that returns a "CartesianChartGridModel", but it's a property of a derived "CartesianChartAreaModel" class that I can't get a reference to other than through the debugger. I guess it doesn't matter because the LayoutSlot that I can view with the debugger does not have its properties set.
I also looked at the Model.LayoutSlot property of the Axis, but its properties were not set either.
Is there any other way to get the position of the actual plotting space inside the axes, or get the screen coordinates of data points?