Since I have nothing better to do currently, I was going to try my hand at making a save game editor for Animal Crossing for the Gamecube; Problem is that I can't seem to find/figure out how the checksum is calculated (though I do know it actually saves the game data twice and the checksum is right after the magic "GAFE" for both times). Anyone interested in helping/informing me of said checksum calculation?

As for what I actually plan in the editor: Everything I can find, if I have the time to.