GM Service Manual Online
For 1990-2009 cars only
  1. With the brake pedal depressed, insert the stoplamp/cruise control switch into the retainer until the switch body seats in the retainer.
  2. Note that CLICKS can be heard as the threaded portion of the switch is pushed through the retainer.
  3. Slowly pull the brake pedal fully rearward against the stop until the CLICK sound can no longer be heard. The switch will be moved in the retainer providing proper adjustment.