At the first waypoint you will need to find the years of
Robert Gilbert's Birth & Death:
Year of Birth – 1504 = AAA Year of Death - 1146 = BBB
Second way point will be N 45.29.AAA W 122.34.BBB
Now you will be looking for G.J. Erickson Birth & Death Years
G.J.’s year of birth – 1522 = CCC Year of death – 1042 = DDD
3rd waypoint will be N 45.29.CCC W 122.34.DDD
Now you will be looking for A. Petterson’s Birth & Death years:
His birth year – 1433 = EEE His year of death – 1042 = FFF
4th waypoint will be N45.29.EEE W 122.34.FFF
Now you will be looking for R.H.H. his day of birth and day of death
Day of birth ( x 12 ) + 17 = GGG Day of Death ( x 36 ) - 3 = HHH
Final location is N 45.29.GGG W 122.34.HHH
There will be lots of muggles near the final location. Be very careful not to get caught.
Good luck and happy hunting