Several modifications to the vacuum line routing will have to be performed when installing the FS-ZE intake manifold to either of the US spec engines. First, the early FS-ZE's intake manifold does not have a fitting for the boost sensor (only the 2003s did). For semi-legal emissions effectiveness and to avoid the "Check Engine" light to come on, you will need the JDM EGR pipe (FSN7-20-310A). The JDM fuel rail also does not have the fuel line pulsation damper built in, unlike the US fuel rail. The fuel line pulsation damper on the FS-ZE is actually located slightly upstream in the fuel line (inlet side) as an external unit. Because of this, you will have to use aftermarket fuel lines for the short section between the firewall and the fuel rail in order to use the pulsation damper (BP4X-20-180).