factory navigation?

hey i've got an 01 sierra and i was wondering if any body has installed the navigation out of an 03 or higher in an 02 or lower, i understand how the 03 and higher bolts in w the 3 screws but i have that down pat with an 03 radio mount from the dealership, but was wondering if i need to look for a factory amp or what, but i just want the nice clean factory look in my stereo,,, any other comments would be greatly apprecieted thanx

You need to go the aftermarket route to have a Nav system installed. The factory radios in the 03 and up GM trucks are a different size, mount and are Class II data units. These factors, especially the Class II problem make it impossible to integrate a factory Nav unit into your 01 Sierra. It would be easier and cheaper to buy a 03 and up truck. sparky