Went rogue! Probably not recommended.
The battery needs service message was appearing
I started the full board removal... but it quickly got very hard and hairy, so bailed and just removed the battery. I don't really care about my speakers though so was ok with putting them at risk of permanent damage. I saw the risk of removing and reinstalling the complete board as much more than losing my speakers. So, I went to town on removing the battery alone carefully tilting my computer away from the motherboard / speakers portion. Took a bit of prying and waiting for the glue solvent to do its job but it came off without an issue. Only issue I came across was after I permanently placed the new battery I had not taken enough notice or care to line up the battery screw holes with those on the board... so, my battery is a few millimeters to the left and the battery circuit board overlap a bit of the rest of the mother board. Seems to be working ok though without being screwed down.
Make sure that you properly align the new battery while installing it.