I think the cut-out pouch is just force-fit in place, no screws
or glue. You should remove all the cork gasket and replace it when
you reassemble.

By the way, it's a pouch so why it squeaks is beyond me. When
originally constructed, there was a short piece of 3/16 tubing
between the two nipples shown. Over the whole area shown was a metal
screen, tacked in place. That was glued over by a gasket. They did
it for a reason when it was manufactured so I try to put it back
that way too.

Jeff Davis
Seattle