If you look at the Keypad_Maintenance Instructions PDF on the AP website is shows how to replace the battery. In my version of the Keypad (pg 10) the display is relayed through a bunch of fiber optic cables that run over where the battery is. The instructions are very clear on how to avoid problems with them. Just need to be careful.
What exactly did you mean by::
... "decided to install a new battery in anticipation of the new software. I did that last month. Not difficult just have to be gentle around the optical cables."
exactly? What optical cables are you referring to here?