Completely different bolt pattern. Unless you are good at fabrication, and figuring out vacuum re routing, I'd stick with what you got, or buy the real deal (Greddy) that comes with all the proper documentation/ parts, or you may be in over your head.
If you were going stand alone, it would be much easier to just do away with all the stuff you would have to worry about getting right, changing out the oem intake.
There is tons of threads on this exact subject, a little here, and alot on the Skyline boards.