I don't know the first Valoy, and I assume that's what your question is about.
Like most others here I have the Valoy II and the Focomat 1c. Indeed both take the same negative carriers. If I remember well the earlier negative carriers had longer pins and no 'window' for the negative numbers. But they can be used on both enlargers anyway. The top half of the lamp head can also be exchanged, and also the extension ring needed to bring the lens down . . .
Great enlargers, by the way! For more than 35 years I have mostly printed 135mm with the 1c. However, I have always had this weak spot for the Valoy II which was my first enlarger. This year I finally turned one into a mature enlarger (like the 1c), reaching up to 20X24 (50X60) easily.