||I could only identify 11 of the 15 elements, but two of the unknown could be determined without decoding, and an educated guess could be made about a third, for which there were only two options. One digit could be determined in this manner, and the choice of coordinates was made by testing it out on Google Maps. I didn't like any of the locations that this placed me, but being unable to resolve this any further, I took a stab at it. Much to my surprise, I got a happy Homer with my first guess. Sometimes a blind squirrel finds a nut.