"...I believe Mears was related to Palmer..."
By related do you mean 'business relations'? Surely its unlikely they were blood relatives since Mears was an orphan from Russia.
He was orpaned at age three and passed between distant relatives, arriving in San Francisco at age eleven.
There his career began, supporting himself with the odd jobs a young boy could find in those days. A stint in the Army during the Civil War brought him to New Mexico, and from there he moved into Colorado and built up the toll road and railroad enterprises we know him for today.
Nick