Had a few spare minutes, so sketched the basics...
Sketch of normal tank viewing angle
Sketch of drains/overflow
Sketch of return plumbing & spraybars
As I was drawing the spraybars, realized they would introduce the potential for draining the entire tank. Guess this is why powerheads are used!! Well, if not spraybars, then probably the fan attachment on the loc-line set vertically.
You will also note how cramped the whole thing is already. Refugium will be a battle. I'm also coming to the conclusion that I will have to build a fully custom stand for all this.