I’ve done it before in older Macbook laptops. Then, they (engineers) changed things! The battery was a simple in/out affair sort of like changing a flashlight battery but with a few screws involved. Nope, not any more. When I took the time to read the instructions, it was 90+ steps and required removing the guts of the computer in addition to disconnecting some very fine connectors. It was heart surgery tough. Fortunately, I was a brain surgeon (in a previous career). Skill!! And nerve! Ego! There is a disclaimer that comes with the battery. Let a professional do it! That’s little solace when you already have the battery in hand. However, this is not for the faint hearted! You can see the old battery. It’s old cells are completely bloated. I came by this realization when I was scanning old slides and noticed the bottom of the laptop computer was rocking. Ninety steps later the computer turned back on. Ninety ++ steps!! The keyboard did not work. Keys? Nope! I missed re-connecting the cable. Disassembly, voila! It works! Then, I discovered the keyboard backlight cable had been missed as well. The instructions are explicit. Don’t forget the cables! But, the cables are tiny. I missed them. Finally, it works. It was challenging. Don’t try this at home. I might not the next time out.