Depends on the flow pattern and lighting in your tank, honestly. Frogspawn (and other Euphyllia, iirc) does like flow, but does not do well in direct flow. In other words, DON'T put it anywhere where it is going to get blasted by a powerhead.... like the bottom left.
If your lighting is pretty intense, it may do well in the lower part of your tank until it gets used to your lighting, then you can move it up gradually. If you don't have a ton of light in your tank, you can put it in the middle or top or whatever. This isn't a terribly picky coral. Good luck!
*edited to add* Your rock work is very nice. I really like what you have done with the hardscape here. This is going to be a really cool tank!