Map Boundry Coordinates when uploading Maps

[ClimbGuy]

I've created two custom maps for the Garmin Oregon, Dakota, Colorado lines.  When I upload the maps I need to fill in N,S,E,W coordinates for the maps borders.  In google earth all that display at the bottom is the North and West Coordinates.  How do I determine the East and West coordinates.  I would like to make the information in my upload correct.

Thank you!  -Jeff (ClimbGuy)

[ClimbGuy]

I followed your advice.  Google Earth still only shows for each of those corners the N and W coordinates.  So I'm assuming I report the N coord for the extreme North and South points and the W coord for the extreme east and west edges?