Changing the Plot Legend (NonSequential Names)

I've got a Chart that serves multiple purposes.  As such, the plot legend needs to change.  I've looked through the forums, and have found options that let me create a dynamic legend of the form (Name1, Name2, Name3).

However, I don't want the labels to be sequential in nature.  I'd like to be able to define the legend as either (x,y,z) or (A1,A2,B1)

Any suggestions?

Thanks!