I have a 1991 civic hatchback, with a 2000 SiR B16A2 engine in it, but with a stock exhaust from the 1991 hatch. I know a catback for the 2000 Si will hook up to the header fine, but not fit on the chassis itself. Do i need to make custom piping?

__________________
1991 Civic DX Hatch B16a Swap:
- AEM CAI - DC Sport 4-1 Ceramic - Custom 2 1/4" Exhaust
- Dropzone Coilovers - Skunk2 Intake Manifold - Aftermarket Fuel Pressure Regulator