The guide could definitely use more details about the proximity housing as well as the camera ring. I used a magnifying glass to pick at the corners and they each popped off. To keep them in place I used a very small piece of double sided tape. I figure they would stay in place once it's all reassembled.
As for completely pulling the camera off the LCD shield like in the picture, if you're going to transfer the shield to a new LCD screen I don't think it is necessary to remove.