How do I bypass the anti-theft on my 2002 cavalier?

Okay, so we had to replace the ignition
recently on my cavalier and after we did
that, it won't start. I have tried everything to
bypass it myself. I've tried the ten minute
intervals, I've tried crossing the battery
terminal wires, I've even tried holding the
gas pedal down with the key in the "on"
position... Please help.