Sean,
The best solution to this I have seen posted, and I have done myself, is have your overflow box in the center. You mentioned that you wanted viewable form 3 sides, well, that may make this difficult. I can tell you however from talkin to a few people about this, that it may not be a big concern for internal overflow boxes as the wave moves fast enough that you dont really lose flow (you may have less water at one moment into the box, but the next moment you have a wave pouring into it)
That being said, I can see issues if you have an external box. As you mentioned, it may lose siphon, depending on the depth of the teeth. I am sure Roger can provide some better insight on this specific case.
Robert.
P.S. Hope the skimmer got there ok.