1. NGK copper plugs, one heat range colder than stock, gapped at .030" BKR7E is the part#
2. Make sure your motor is in good working condition
3. If your clutch is already on it's way out, it won't last long on the nitrous.
4. Change that timing belt before it snaps and you need a new motor.
5. Go by the Zex directions and start at the 55 shot, and work your way up.
You don't really need a fuel pressure safety switch with the zex kit, since it regulates the pressure it adds according to the pressure of the nitrous. Tuning is the key, but it's not hard. A few degrees of retarded ignition timing on the 75 shot and you're good to go.