I don't think the standard street header has a wastegate flange. At least it doesn't on the webpage picture.
If I was going to buy a header I would get the Rev-Hard race header, since I got rid of the A/C. Equal length, stainless steel, it doesn't look as buff as the Kiwi, but it works just as well if not better the than the Kiwi Street Header at less price. It has a wastegate port. There's a drag 4th Gen Prelude here that has one, with 2.5"->3" IC piping. It's pretty damn cool.
Now I'm just rambling, but judging by the picture I assume the mounting position is very close to the F-Max manifold.