Some "general" tips on Disston saws, Hand saws will have 5 nuts, panel saws less than 26 inches will have 4 nuts. On panel and hand saws Disston usually stamped tooth count into blade, at left heel, although they can be faint at times. If you find a Disston panel saw with 5 nuts it most likely been cut down, but depends on age. Your saw looks like it has plated nut which would date it after 1948, although the handle shape looks older than that. The handle should be apple wood. It definitely looks like cross cut saw. It may well be worth doing a good restoration on.
