This challenge is pretty straight forward. You must have found at least one cache in states that touch forming a path from the Pacific Ocean to the Atlantic Ocean.
All previous finds count. The finds don't have to be on the same trip, day or even year. The easiest way to verify it is to look at your stats page on geocaching.com and see if you can follow your filled in states from one ocean to the other. If you go with this option just note it in your log and I will verifyit. If you are not a premium member or for some other reason don't have your US states map showing, then please post a list with the caches and the states you are using to qualify in your log.
Sorry for this one Alaska and Hawaii don't help. The west coast is defined as Washington, Oregon, and California and the East coast any of the costal states from Maine to Florida.
As for the puzzle subtract the total number of states in the USA from the listed North and West coordinates to find the final location.
Here is my map showing a qualifying path
