There will actually be indentions in the framing of the radiator support/front frame that match the 2 1/2 intercooler piping, go a bit lower than that and it should go in nice. Along with some trimming of the inner bumper piece. I welded on the supports for the IC.
Check out my CarDomain pictures to see what it looked like before and after.
Link-els
http://www.cardomain.com/ride/2368044
It almost seems their was supposed to be one there already! F'ing USDM market...
Edit - PS, you did so good on your tune, you can tune mine in next time I have to!