Very clever HIFI. So it will look closed up whether the speaker is up or down. And since the two doors open opposed to each other, the lift mechanism could be a electric linear actuator that hooks below the two speaker platforms. When it lengthens it will cause both doors to open up until the speaker platforms fill the open gap. Any suggestion on a speaker to use? Something low profile so the doors do not have to open say maybe more than 45 deg.
You are all over this design.
Speakers you ask . . . I know what I would use but you should pick what brand you like. Because they are so far away from your cockpit system mixing brands would not be a concern. They wont effect what you are staging at your helm. They are clearly in a separate zone. Because this is custom you have the luxury of picking something that works in these triangular shaped baffles. I would go marine grade here because the environment is harsh compared to your cockpit. I can recommend a two way separate with separate crossover. I pound on my separates and they simply perform.
Here is a start : http://marine.jlaudio.com/products_components.php?prod_id=425
Your other choice would be Coaxial design. I just don’t know what kind of size you will get away with. I like your idea of 45% but you may get away with less, you may need more lift. You will want a dedicated amp for sure.