The speaker housing is held with Phillips screws to the trunk lid. Some of them (2 or maybe 3) are hidden under the large black inner lid cover. That's the inner cover held on by a load of screws.
Once you drop the liner you will see the last screws for the speaker cover.
Yesterday, I removed the inside of the lid. There were 2 screws on each side of the lid that screws into the speaker housing. When I unscrewed them the nut plates dropped into the speaker compartment. They were found magnetized to the each speaker. With some finageling I was able to retrieve them and det it all back together.
My problem is removing/separating the actual speaker compartments from the lid. With all screws removed the black housings still are connected (they may be pressed into the edge of the lid but did not want to force it???