During reassembly, follow this step to replace the plastic shim that runs across the bottom of the midframe and loudspeaker. If you don't have a replacement, press the old one back into place.

Remove the clear liner from the shim.

Use the markings on the midframe to align the left side of the shim and press it into place.

Use the flat end of a spudger to firmly press down along the whole shim to secure it.

Remove the blue liner.