I found the plastic pull tab to be useless. Peeled pretty much the whole battery out from the left side. Used a probe to "break" a few strands of glue to help. Just watch the connector and ribbon cable in the lower left corner as you pry up so you don't crimp them or damage them.
The spring contacts on the speaker bottom make re-installing a bit tricky, since they make the speaker pop up until the screws are back in. If this happens, one or more of the fingers that are supposed to be under the case will pop out. What I found worked was to put the speaker in, getting the metal fingers under the case as directed, and then hold the speaker down with while putting the two screws in, along with that triangle piece.
Bump on the comment re: no picture here shows the proper cable route. The text mentions being careful to route it under the metal finger, but no way to know where that it is from these pictures. The re-route is: around the left side of the screw socket and then the right side of the silver thing (finger) which is to the right of the battery connector.
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