"To reconnect, align the connector carefully over its socket and press down with your fingertip—first on one side, then the other—until it clicks into place."

This is ambiguous because it isn't clear to readers which is the 'side' of the connector referred to. For example, with a long rectangular connector, do you mean one of the short sides, or one of the long sides? I fear I may have got it wrong - after replacing my iPhone XS battery the bottom speaker no longer worked.

I disassembled the phone and disconnected and reconnected the connectors, to no avail, so reassembled the phone and ordered a replacement speaker. After fitting that, the speaker still doesn't work but unfortunately my screen now has a very bright stripe a few millimetres wide down the RHS. I didn't apply any excessive forces while lifting the screen and working on the phone - in fact it was easier to remove than the first time I opened it. The only thing I can think of is I used excessive isopropyl alcohol when cleaning the seal off.

My model (with control buttons at the top front, either side of the lever) is designed to remove the right cover (looking from the spout end) first.

On my model, it is necessary to first pry off the spout cover, held in place by a clip either side and one at the top, offset to the left as you look at the spout.