2 problems: First, battery losing life, then computer could not communicate with hard drive.
Went well. The drive cable was a bit of a challenge because of the need to bend it at sharp right angles to fit stair-step in upper case where it gets fastened with screws, but after several tries, got it to fit. Battery replacement was easy once I go the 3-point screwdriver to remove and install the battery hold-down screws. The computer works fine after the repairs
Be prepared to make the right-angle bends needed in the drive cable