You can just use the harness that's are already in your car. You may have to add/extend a few wires, but it is basically plug and play. You already have VTEC, so that is one thing you won't have to worry about. As for the ecu, your car is obd2a. If your are staying obd2a, then get an ecu from a 96-99 Integra....that with plug right into your stock harness without the need of any conversion harness.