You'll need replacement adhesive to properly reattach components during reassembly, so make sure you have it before proceeding.
Prepare an iOpener and apply it to the back cover for 2 minutes.
Attach a suction handle to the back cover's lower edge, as close as possible.
Apply more heat if needed to soften the adhesive further. Be cautious not to overheat using the iOpener.
Insert a second opening pick along the bottom edge of the phone.
If the adhesive becomes hard to cut, it may have cooled down.
Insert an opening pick under the top left corner.
Slide the pick along the top edge, slicing the adhesive.
Leave the pick in place at the top right corner to prevent resealing.
Clean relevant areas with isopropyl alcohol (>90%) before proceeding.
Use a stack of heavy books if necessary to aid in bonding process.
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