My father was adopted. I believe that I have located his mother. Her father is my GREAT GRANDMOTHER's first husband. I have tested 3 1st cousins once removed??(Female 1 cm=673 on 29seg/female 2 cm=644 on 32seg/male cm=461 on 20.) on that line. My GREAT GRANDMOTHER*'s 2nd husband, I tested 1 first cousin once removed? or half first cousin once removed? (Female cm=615 on 27seg)? How can I identify which one of these husbands is my great grandfather?