Hey for alittle run down of the rpo codes and non lux and lux(i just did alot of research as i put one in my truck. Ok on ebay olot of people will say atleast of the following:
Option 1
For vehicle with RPO Y91 or Y92...This is for the Bose LUX packages that come in escalades, denali, and some hummer H2's, but not all hummer H2's
Option 2
For vehicles with RPO UQ7 or UGA(i believe its UGA)...These are the vehicles with non lux Bose. These are the silverado's, tahoe's, etc etc..
The only difference in the non lux and the lux is that they have 2 different bose amps in the middle console. The LUX amp runs off smoother and sounds better supposedly(some people swear that its better, and ive heard people that upgrade them and say that they could tell a difference but that it wasnt like everyone made it out to be). Now thats not me saying that, and thats upto you.
The nav unit youll need is 15800000 By delphi if you have the UQ7. I just installed this into my truck. And the nav unit for the Y91 or Y92 is 15800001. There are other model numbers out there, but these are the 2 main ones.
If you feel compelled to upgrade to the LUX nav unit, then you can do this as well. But youll need to install the Bose LUX amp, and also get the LUX Nav unit. This requires alot more wiring, and alot more money. You can also install the 6 disc changer as well with either.
Now just look for one that says its compatable with your vehicle, the sellers i emailed insured me that even though the product number was the same for the head unit that it will still work, and i want to believe them because most of them sell tons of these units and know what they are talking about. I found one that was takin out of a vehicle as soon as the vehicle was pulled off the lot, they posted it as new...but when i got it it still had the vin stored. I just got done installing yesterday and have to wait to get it cleared at the dealer tomorrow. Hopefully this will help undersand alittle more. Oh yeah, look for the vss wire. Do a search of vss wire on here to better understand