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I am wondering if anyone knows how the 8 digit number identifiying the individual maps in Mapsource relate to their location.   for example, the last image in mapsource east disc.  is numbered  05624730    and covers 48* 30' to 48* 38'  lat   and  92*30'  to 93*00'  lon.   and corresponds to CRANE LAKE, MN-CN (WEST)   Topomap   in mapsource.   any help would be appreciated