Hi Dean, I received my link ecu yesterday and will put it on an Impreza Sti 2000 too.
I'm planning to add the IAT in one of this 2 location.
Talked with some guys and they are using in that way on the oem sti IC. They drilled a hole and added threads. Will do the same, I think that will be better than weld something. Will try to attempt the first start after Christmas.