12- Remember you have to have the gun barrels poking through the Low bocage or they won't have LOS, as this view confirms when I moved them backwards a little-
13- but if all the other guns are moved back a little they DO still have LOS over Rural, Brick and Hedge even if they're not up against the wall like this-
Conclusions-
a- ATG's (including the tiny 45mm) have LOS over Rural and Brick walls, Hedges, and through Low bocage.
b- The guns only get partial cover because their gun shields stick up like sore thumbs over the walls and hedge, but that might buy them enough time to fire first before the enemy spot them.
c- Low bocage is the best cover because it's tall and the gun shields don't stick up above it.