Replacing Stock Radio on Denali

I wanted to replace my stock radio with a navigational system, but after i was told of all the changes that I had to make and how it may void the warranty on my truck for the radio, I changed my mind and decided to leave it stock. One of the problems was that if I got a head unit with XM, I would have to replace the existing XM antenna because it would not be compatible with the head unit or the new XM module that I would have to buy. The other problem was the controls for the steering wheel may not work, the OnStar feature may not work. I hear of interface modules that would correct these problems. Has anyone installed a new head unit and maintained all the original features ie...XM, OnStar. I was looking at the Pioneer AVIC-N1

I take it you have a pre-'03 Denali? If so, then yeah, you can't retrofit the GM nav unit w/o lots of work and parts--not that it can't be done, but it'll require a lot of work and parts.

OTOH if your Denali is '03+, then it can be easily done...again, as long as you have the necessary parts; the only sticking point may be the type of audio amp that's in your truck.