I personally adapted to the keyboard. It is definitely a bit different.

I was looking at replacing the pram battery on my machine, so disassembled a spare to identify the pram battery before buying a replacement. Unless I'm doing something wrong, it's a hassle to get to. It is located in a compartment above the left battery bay, and connects to the top case where the trackpad is. To get to this, you might kinda sorta be able to pry up the top part of the case after removing the 4 front keys. However, to get easy access to it, you need to remove the entire top case from the machine, which involves removing the LCD among other things, which requires removing the display access panel that seems incredibly sensitive to breakage.