illumination for steering wheel radio controls

I was wondering if anybody out there knows how or if the lighting for the steering wheel radio controls can be changed or how to go about it , it is a 2001 chevy s-10 blazer with the trailblazer package . Any help would be appreciated . does the entire swich assembly ( volume mute ) have to be replaced ?

I looked at my steering wheel controls, I didn't see any bulbs, but if they're in there, they're like all other switch bulbs... SImply desolder and solder in the new ones.