After much reading here I have my eyes set on one these clocks. The iterations do get confusing. Great references to identify age by case, wood and yes even Phillips screws. Is it possible that a movement would exist without any markings or numbers on the plates? Am I correct there were four models, 61, 77, 77A, and 77B. Is it safe to assume that the movement is not authentic if these numbers are not present? Don’t have the resources to make this kind of mistake. As always thanks for helping a new guy out.