The Kartboy hangers are very hard to remove. In one of our install days locally, one of the members had an OEM rear lip and we were installing the HKS CF-Ti exhaust system. We put on the Kartboy hangers and realized it didn't fit. Took us about 10 minutes to take it out using a pick. Didn't really damage it but still a pain in the butt. When you're putting them on, the edge is tapered and rounded so its no chore but going out, the edge is flat and tight.