First thing you'll have to do is locate the headstone for Martha Daniels. Using the information on the headstone, you're going to fill in the following letters to complete the the coords for the final stage, which is located real close to the headstone.
The cache can be found at N 42 29.ABC W 089 40.DEF
-If the stone is brown in color, A=5. If the stone is gray in color, A=6.
-Take the last two digits of the death year and add the last digit of the birth year to it. The sum will be known as "BC".
-Add up all four digits from the year of birth. The sum will be known as "DE"
-Figure out what age Martha was when she died. Take the two digits of her age and add them together. Now subtract the third digit from the date of death. Your result will be known as "F".
Please be respectful of everything while here. Please do not hunt this one after sunset. There will be no need to move or lift any headstones or grave markers. Access to the cemetery can be gained by simply removing the chain that holds the gate closed. There isn't a lock, just a chain. Use the checker to confirm your coords.