1993 Chevy Corsica

Hello -

We don't show a button to depress for the ignition switch.

IGNITION SWITCH
Removal
Disconnect negative battery cable. Remove trim panel(s) from base of column as necessary to access the ignition switch. Remove dimmer switch, if necessary. Disconnect electrical connector from ignition switch. Remove ignition switch from actuator rod.
Installation
Install and adjust ignition switch using adjustment procedure. See IGNITION SWITCH ADJUSTMENT under ADJUSTMENTS. If dimmer switch was removed, install and adjust dimmer switch using adjustment procedure. See DIMMER SWITCH ADJUSTMENT under ADJUSTMENTS. To install remaining components, reverse removal procedure.

Are you talking about the lock cylinder

LOCK CYLINDER
Removal & Installation
Remove turn signal switch. See TURN SIGNAL SWITCH. With ignition key removed, remove buzzer switch. Insert key into lock cylinder. Turn lock cylinder to LOCK position. Remove lock cylinder retaining screw. Remove lock cylinder. To install, reverse removal procedure.