I have a buddy who did this to his car. All he did was buy a 2015 Nismo bumper, painted it and installed it. He said no additional fabrication was needed. I seen it today and it sat perfect. Just be careful with removing and installing the bumpers so you don't break any tabs. One thing that i did notice is that it was a little flimsy like he forgot to bolt something in on one side.
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Z34 09 #0419: 3M | Pioneer | Swift | SPL | BERK | Stillen | Z1 | VOLK Racing | Project Kics | Tommy Kaira |