But not so much when there is 720 sprites, from "x00y00" to "x20y38", to lay down...
Omg, this is a horrible idea! You need one sprite with 720 instances, not 720 different objects!
You can define instance variables on this sprite, say gridX and gridY, to identify position of each tile in the array. And of course, fill these values programmatically, not manually.
Another option is to use a tilemap. Tilemap is basically an array. On click change the tile under mouse cursor.