One of the key elements in determining when Susannah Rucker died in Amherst County, Virginia, was the date of the deed where her heirs apparently sold the farm on which she lived in her widowhood.
The problem is that the deed was transcribed incorrectly by an early researcher. The deed was written in 1781 and finally recorded in 1791. The numbers are pretty clear and there's a reasonable reason why it took ten years to record the deed. The earlier researcher either transcribed the date incorrectly, or assumed the deed was executed in the year it was recorded.
We'll see why it took ten years to record the deed and how it all helps estimate when Susannah Rucker died.
And, in all honesty, a year of death of about 1781 is a little more reasonable for Susannah than 1791.