For swapping a k20 or k24 engine in the FD1 chassis you would need the following:
1- Mounts from the same model civic si from USA
2- K20 engine wiring harness,new one retails for $270 from USA
3- Dash harness from the same model civic si from USA
4- Aftermarket header for 2006 civic si (skunk2 sells one around $800)
5- flashpro needed,k-pro wont work with your wiring
6- You would also need a civic si radiator
7- Would need shifter cables and shifter box from the civic si
8- Both sides axles from civic si
9- Would need some fiddling with the fuel lines,and an fpr is necessary,nothing too big to worry
10- Just to let you know you can only install the k24a2 DBW version in the FD chassis or the newer versions of k20z1's which
also feature the same DBW versions.