In a message dated 8/11/2010 7:38:43 P.M. Eastern Daylight Time,
inua@CHARTER.NET writes:

On my 91 Carat (auto tranny) there is mounted below the dash, that  is
actuated by the brake pedal arm. It is not one of the brake  light
switches - they screw into the brake master cylinder itself, but this  is
actuated by the pedal action itself. When the pedal is at rest  (no
brakes applied) the pedal arm pushes the switch "In", when the pedal  is
depressed, the action is to release the switch. It has one  elctrical
connection n one end, and it appears to have a vacuum hose  attached to
it as well.

cruise control switch..