This is the most difficult part of the entire exercise. On my iphone6s it took 10 mins for the first unbroken strip. The second strip broke and it took about 5 hours. It still wouldn’t come. I came close to emptying out my 10 yard floss and still no luck. The only way I got it out was by feeding the underside of the battery with isopropyl alcohol 70% (I didn’t have the 90% that they recommend in this guide) and let it soak overnight. Voila. The next morning was a charm. It just came right off.

In hindsight, I would have just soaked it lightly with isopropyl alcohol, let it rest for a couple of hours or overnight and not have to bother with any string tugging, pulling and flossing!