That is a one piece unit that is welded shut. Plastic welded, but non user serviceable parts. Those are LEDS.
They probably are not burnt out, something is disconnected. Pull the front off the dash and remove the unit
with the lights and controls. Use a small screwdriver and pop it open. You can see inside and may be able to
replace the lights if it is truly burned out. Radio Shack will probably have the lights.