no special tools required 🙂
if you can fit a timing belt, you can replace the z22se timing chain 🙂
quite easy to do, but allow a day just in case.
basically remove cam cover, jack up engine, remove crank pulley (very tight - use a long bar and have someone press the brake pedal whilst car in gear)
then remove chain cover and all is revealed.
get a haynes manual too 🙂