I'm trying to create a drop down control for each cell that will present the
user with values Red, Green, Yellow. Once selected the cell will turn that
color.

I don't want the cell formatted based on it's contents, instead based on
what the user chooses from a drop down.

For example, the cell contains "Fred". I want a drop down on that cell lthat
allows me to choose "Red", "Yellow" or "Green". Once selected the "Fred" cell
turns that color.