Naval unit questions.

[RifleMech]

Hi,
I'm not sure where to put this since it involves a couple of books but I had a couple quick questions about turrets on naval units.

TM p 107, p 137
TO units and equipment p  71, 158-160

1) Can a turret be placed on the bottom of a naval unit?
Like the bottom turret on the Arcadia? https://bbts1.azureedge.net/images/p/full/2020/09/4b71145b-e847-4cd6-92de-658ce72e51e1.jpg


TO p57
This is probably answered but I'm not seeing it.
2a) A Templet E ship is 9 hexes long 3 levels high and 3 levels deep. Is that a total of 6 levels high from bow to stern or does the height very above water but the depth under water is flat?

Basically is the Deck at level 1, any turrets at level 2 and the bridge/superstructure (presumably being in the center) hex being the highest at level 3? And the bottom being flat at level 3? Or would that be a Mobile Structure?

2b)
Depending on the answer above would a lower superstructure such as that on the Yamato be considered; fluff only, the lowest part of the ship at depth 3, or the lowest part of a Mobile Structure at Depth 3? https://lh3.googleusercontent.com/proxy/BGTDfbHlufB5n9zGqfqxbFtV_7e_sS7uumsqdTUXrlD4O9Ro6JcS5h-q-J20UZXwE2FmpeJyutkXQLFTY3dX2HuVtRUzg7WCDdKWAgMxxT96fG_ociPSNFuKoufD


Thanks :)