ShortCutKeyDisplayString for dropdown TextBox?

VS2008, Win 7.
I need to create a toolstrip Dropdown with 1 or 2 Textboxes (which I can do), but with the ShortCutKeyDisplayString (which causes an error!).
I have seen a while ago here (by Nick Thissen) the Renderer Class used to modify some of these properties but have no idea how to go about this one, or even if it is possible.
Can somebody please advise.

I can answer this myself: I have discovered that I can use a UserControl to add a Label and Textbox together, which solves the problem.