I've got a full Full-Race setup (downpipe and cat-back) and I found it very difficult to get everything to align "just so". I think I've been under the car about 4 times total to tweak where things are at. I'm not sure how your cat-back portion attaches with the N1, but with Full-Race it has a slip coupling that you can turn any which-way and slide back and forth. I eliminated *most* of my rattles with proper adjustment at that coupling and the next and by putting a giant HVAC zip-tie around one of my hangers to cinch it up a little bit (should just get some poly hangers, but it's what I had). I'm honestly a bit disappointed with how difficult getting things to line up properly has been, but otherwise have been very happy with the setup. Quality parts, but the clearances for a 3" exhaust are so small that it doesn't take much. I see poly hangers in my future...