Eakinsme, it is a bit more than just loading up a save. You have to install a dashboard exploit if you do not want to load the evox save everytime. Also, you need "Pheonix Bios loader" (pbl) to load the bios, otherwise you won't be able to open the disk tray or load backups, emulators, etc..(without signing).
As for the save, you copy it onto the xbox HDD from the memory menu in the original dash, so the save loads from the HDD and not the memcard.