Yes I know it is the original, but it is not the point though, it is the principal of just putting it back together the way you started. The CR2032 is a big battery and i tried it in my my own copies of Ruby and Sapphire and it bulges the case but the case will go back together and fit *snugly* into a GBA slot and it does work. As stated in the guide try to use a CR2025 or a CR2016, they should fit better with the case.
No, replacing the battery doesn't erase saved data. It just starts up timed events again and gets rid of the "dry batter" message.
Sorry for the delay, but in order to make sure you don't strip the screw, i would suggest buying the Tri-wing screwdriver. Besides you never know when you may need a Tri-wing in the future.
and it allows the player to transfer to diamond and pearl again