Dual AC control replacing stock single control?

How hard the the change, if at all doable, in my base model 2000 impala?

I did it. it was pretty easy. when it was in, it wouldn't do the dual air zone. whatever you wanna call it. someone else told me in this forum that you have to change the airbox under the dash too.

thanks...to much work for me, the wife will just have to deal w/ it being colder than she likes on our next roadtrip...LoL