Chart default colors in 2007

I have a lot of charts to create for my thesis and I'm supposed to use only certain colors that are specified by my university. These charts are coming from several workbooks. Is there any way to create a chart style or edit the default color palette? The only information I have found says to go to Excel Options>Save>Colors and change the colors that appear in the bottom two rows. The problem is, the colors in the bottom two rows are not the ones that appear in graphs by default. Any suggestions for changing only the colors and maybe the line thicknesses?