There are a couple of threads from 07-08 that cover this.
I have swapped out my steering wheel and pulled both the control switch sets out for painting. Its not difficult.
The book says you should pull the battery terminal for safety however I have done mine three times without doing so and it was not a problem. Even my GM World Class tech told me that its normal to remove and replace the steering wheel without pulling the power.
If you sit in the drivers seat and face the steering wheel, by looking at the left and right sides fo the steering wheel from the side, you will find a small hole on each side, in front of the wheel spokes. These holes are access holes for releasing the locking clips for the airbag. Use a phillips head screwdriver or an allen wrench inserted into the hole to push the locking clips free while pulling out on the airbag assembly.
Once you have the airbag assembly unlocked from the steering wheel, you will see two cables / connectors that you can unhook and remove.
Once the airbag assembly is removed you will have access to the cabling and retention bolts for the steering wheel controls. To replace one, remove the bold for that side and pull the control assembly out of the steering wheel. You can purchase a replacement control assembly from Crate Engine Depot or the GM source of your choice.
I bought a replacement steering wheel from
that included the control assemblys