5s Battery Replacement Kit should include iSclack!
My father-in-law gave me his old iPhone 5S when he upgraded. I wanted to sell it, but the battery wouldn't hold a charge.
Despite reading about the care needed to avoid popping the screen up too far when lifting the glass with the suction cup, and depite taping the glass to the back to limit motion, the front did pop up suddenly, pulling my safety tape off (!) and damaging the home button cable. Otherwise the repair went well (one glue strip came off intact after heating the back with a hair dryer, they other broke and took some work). So when I turned the phone on, Touch ID could not be enabled and the home button did not work. Other than that, perfect. After a little research, I enabled the soft home button built into IOS 11 accessibility, and found that it was really just as easy as the mechanical button (though no Touch ID). I listed it on Ebay and sold it within 30 minutes for $59 - less than if the home button had worked, but more than enough to cover the iFixit kit, and to make my exploration into the innards of an iPhone worth while.
I wish the iSclack was included with the 5S battery replacement kit - from my experience and reading reviews, it is obviously risky to try to open the iPhone with a single suction cup. I would have paid more if I had known.
Get the iSclack to separate front and back of your iPhone - don't trust a single suction cup - or be EXTREMELY careful to control the opening.