No brake lights on 1998 Silverado
Tail lights and flashers all work
I believe that is is located under the dash on the steering column and you will see it makes contact with the brake pedal. It does look like a bracket, that wraps around the brake pedal arm. When the brake pedal is pressed down it pushes the cylinder switch together which closes the circuit and makes you brake lights come on. Check your fuses as well as your wiring to the brake light housing. Also make sure that you have working bulbs and the right bulbs are inserted. Sometimes, the bulbs look identical but the bulb will not make contact with the housing connector. Here is a nice explanation how to check the circuit. Hope this helps a bit, good luck.
The brake light switch is on the arm from the brake pedal to the brake booster (under the hood). It is held in place by a snap clip that is nearly impossible to get off, so don’t. Buy your switch and a new snap clip and then take a large screwdriver and shove it between the top of brake petal and the switch. Work it in there and then pry the switch off the petal! That clip will resist for a little while but it will pop off. You may never see it again. After getting the switch off, work it forward until you can get to the plug and unplug it and hook up the new one. Work the new one back in place making sure the hook on the back fits over the brake booster arm and then snap it in place. Now to get the snap clip back on I use a long skinny screwdriver with double sided tape on it to get the clip in place over the knob that holds the switch and then use a second screwdriver to snap it on. Still a pain to do but this has worked for me.