iFixit

Use the edge of a plastic opening tool to pry the dock cable up from its socket on the logic board.

Peel the dock connector cable off the adhesive securing it to the logic board and the side of the speaker enclosure.

Use the edge of a plastic opening tool to pry the cellular antenna cable up from its socket on the logic board.

De-route the cellular antenna cable out from under the metal fingers attached to the logic board.

Remove the two 2.4 mm Phillips screws securing the speaker enclosure assembly to the outer case.

Remove the small black spacer that was under the Phillips screw near the vibrator.

Use a plastic opening tool to lift the speaker enclosure assembly out of the case, being sure not to damage the EMI fingers on the attached Wi-Fi antenna.

Remove the speaker enclosure assembly.

Before reinstalling the speaker enclosure assembly's screws, be sure the Wi-Fi grounding fingers are installed below the lip in the iPhone's metal case as seen in the third picture.

Before reassembly, be sure to clean all metal-to-metal contact points between the grounding fingers of the Wi-Fi antenna and the case of the iPhone with a de-greaser such as windex or isopropyl alcohol. The oils on your fingers have the potential to cause wireless interference issues.

Remove the two 1.6 mm Phillips screws securing the cellular antenna to the speaker enclosure.

Starting near the cellular antenna cable, use the edge of a plastic opening tool to peel the antenna off the speaker enclosure.

Continue peeling the cellular antenna off the speaker enclosure, being careful not to rip the gold bracket attached to one of its edges.

Remove the cellular antenna.