How do I index a family register?

diannenielsen1

I've indexed Irish records for several years, usually baptisms, sometimes marriages and occasionally death records. I just opened a batch labeled "register." It shows families, a treasure trove for temple work. It has parents and children, with 3 digit numbers beside each, but no date. How could I index this? Seems like a genealogy gold mine, but it doesn't fit any indexing formats I know.