How to change the thermostat in 2003 CTS

Hello i have the mitchell on demand software and even it doesnt show where the thermostat is on the cts 2003!
Does anyone have any good info on how or the specific steps of what to remove to dig it out?
 
thanks

It is located under intake plenum, need to remove top of intake and runners to get to it.There are also some brackets to deal with this is not an easy repair might be better to take to dealer.