I know little about my Nimmo and Rankin families.  I'm looking for a William Nimmo married to an Agnes Russell.  They had a daughter, Jean/Jane, who was my great-great-great grandmother.  
The Rankin connection is even further back.  It is Janet Rankin married to a James Nimmo.  The parents of William, I believe.  
My research keeps me in the Bo'ness and Linlithgow areas.  I wish I could help with the connection between the families you mentioned.  My connection might now be correct.  Hope someone can help me, too.
Thanks.