Just use the civic harness..What trim is your civic (EX,DX....)?If you have an EX model its just a bolt-in process.If you have a DX or anyother non-VTEC model its just as easy but you need to wire VTEC.Your going to need a complete change over.Also i forgot,your car is obd2b(i maybe wrong,im a EF guy) so depending on the year of your motor you may need to change the obd of the motor.