Start at the posted coordinates and proceed down the drive passing about 12 trees in the median. After the 12th tree explore your surroundings and you should spy a couple utility boxes. On one of the boxes you should spy an American flag. Above this flag is a letter and three numbers. Proceed as follows.
If it's F009 then proceed 100 ft at 270°
If it's T005 then proceed 600 ft at 271°
If it's P001 then proceed 90 ft at 0°.
Please Don't take the stamp that is part of the letterbox. It is to remain in the letterbox