how to change the z-order of series (or datapoints of a series) in a chart

Question

Hi All:

I am using vb.net 2008.  I have a chart with 4 series.  They are as follows:

Series 0:  FastLine (about 100 points, of course no markers)

Series 1: Fastpoints (with 10 points, and markers showing)

Series 2: Line (with 2 points, and markers showing)

Series 3: Line (with 2 points, and markers showing)

These series are plotted as outlined above.  Also, for series 1, 2, and 3 I use the tooltip to show the coordinates of the datapoints.  Now, in my program, if all the 4 series cross the x-axis at the same location, I would like to be able to tell the user the coordinates of the intersection.  However, since series 2 and 3 are on top (with their datapoints not on the x-axis), the program displays the coordinates of these 2 series, rather than the coordinates of series 1 which actually has a datapoint on the x-axis.  I know that for charts, the z-order of series is controlled by the order in which they were created.  Now, I was wondering if there is a way to bring a particular series (or even datapoint of a series) to the front by changing its z-order?  If not, I guess, I will change the order in which they were created.  I would appreciate any code.  Thanks;

Bob