Where is brake light switch on 1991 corvette?

On a 1991 Corvette, the brake light switch is located on the brake pedal assembly itself. It's a small switch that's usually mounted directly to the pedal, or very near it. You'll likely need to look under the dash, near the brake pedal, to see it. It's often a plunger-style switch that's activated when you press the brake pedal.