Remove the wire from the switch
Unscrew the switch and remove it
Stomp a couple of times on the brake pedal with the engine running...
Replace the switch and connect the wire
The light should have gone out...
If it still lights after the above process, the wire might be grounded by being pinched perhaps when work was done..or...the switch pin that sticks out of the end of the switch that screws in may be bent of broken off...grab another switch and try again.
