Nice job. I looked into doing this on my 08 V8 as well over a year ago and still have not done it. If you follow this link...
http://www.thenissanpath.com/viewtopic. ... sc&start=0
On page 2 towards the bottom, user forgottenzone installed one on his V8. He was able to work the box into his system. He didn't post it, but through PMs I was able to find out how he did it. Here is what he told me...
Forgottenzone..."All modifications i had to do. The bolt hole inside the filter box did not match to the hole on the pathy fender well. So either drill the bottom of the box plastic to match the pathy bolt hole or simply use sheetmetal self taping screws with washers and screw into the well.
when you take off the OEM box, there is a bolt mount that is next to breaklines next to the fender wall. When you remove the oem box you will see the piece of metal sticking out with has a nut welded to it where the oem box gets bolted to. It sticks out and it wont let you mount the box properly. What i did was I used the grinder with metal cuting wheel and i cut it off. This will alow the box to sit nicely on the fender. Last thing you need to do is go to lowes or homedepot, and grab some 1 inch thick foam insulation tape. They sell them in the insulation isle for insulating windows doors. there is going to be about inch inch and a half space between the fender intake whole opening and the air box opening. I used the foam tape, taped it all around the hole on the fender. Made 2 rows of tape one on top of the other to make it thicker. then mounted the box. this will give you a good air tight seal. Thats it."
Hopefully this might help if you wanted to put the box in. I'm still debating to do this mod or not. I've not heard back from forgottenzone in a while.