Super easy fix that made a massive difference
My battery was original to my early 2008 MacBook and had actually ruptured days before I put in my order to iFixit. I've repaired a number of iPhones now with iFixit parts and tools, so I was confident this job would be a cinch.
Literally two steps. Can't beat it.
You don't need a fancy coin to open the battery lock. A penny will do.