[NTG-context] text over text

I am typesetting some transliterated medieval German and need to place one letter, e.g., an “e” in scriptsize over another letter, e.g., a “u” in text size. I have managed to get this in italics using \mathstackers and \definemathmatrix, but I need both letters in roman face and at text size. Is there a way to do this or would another approach be better? Alan