Is it possible to turn a notehead into a letter?

I'm wanting to replace note heads with any letter of the alphabet for a personal project of mine. I've found I can easily change them to possess the pitch names and Solfege but that's not exactly what I want. I want a similar result to those but I want it to be my own customisable letters. Say for instance I want an F to show the letter T but I want another F to show the letter W, I'd want to be able to do that. Is there any suggestions or is this impossible without a plug in?