need 3d surface charts with red=$ loss, green= $profit

I'm developing several charts for a financial modeling program and can't find a way to get my charts to graph in two colors. The legend always comes up with at least 3 or more colors. I have the same problems in both the 2 dimensional surface charts as well as the three dimensional surface charts.

I need these charts to show the loss area of the graph in red and the profit area in green.

The data source is about a 20 cell by 20 cell area that sums up 5 other similar areas. The values are dynamic so the amount of proportion of profitable area vs. loss area can change dramatically from chart to chart.

Any books, websites, or programming examples would be greatly appreciated. (I have five excell books in my office and can't find anything to do this.)

Thanks,

David
davido@wctatel.net