That's funny, I'm trying to do just the opposite in my YXL... put IN a stock CD changer in that cubby hole.
You must have a 'Nali. Otherwise, you could pick up a Silverado, Sierra, Suburban, Tahoe, or Yukon NON Denali center console trim and replace the bezel, which would net you two open and rubber matted cubby holes instead of one, as well as two charging ports instead of one. However, the upper console trim needs to match the lower console trim, so it would involve changing the entire center console.
One thing you might do is consider an in-dash computer... basically a single din unit with a slide out tray 6.5" to 7" touch screen, that once slid out, reveals a disc slot for various types of data that might be enjoyable to have in your car... like navigation, mp3s, mp4s, mov, avi, and other types of files.
Various websites are dedicated to this... incarpc, carmp3, those arent the exact names, but a google search will get you there. You can even rig it to WIFI, or tether it to a smartphone for internet everywhere. I found a great one that I was going to use about 5 years ago, but then it wouldn't be integrated with my OE factory Nav system, and having that OE navigation, along with new smartphones, kind of reduced my steam to go aftermarket.
So I'm going retro, while you might consider going forward. Your Denali cubby might have to be slighty enlarged to fit a single DIN device, but it would be cool.
Cooler still would be to move your HVAC controller down that cubby area (the HVAC is of relatively shallow depth, but has a taller and wider faceplate than cd changer, so some modification is required), and then mount an iPAD in the area that the factory (and your current aftermarket) radio and HVAC controls used to be. That would be the hottest setup. There are several videos on YouTube of guys who have done this, and in some cases have REdone it even better.
If I were to start over, that would be the direction I would consider.
Finally, one low cost, low tech way to fill the spot where your CD changer used to be... is, after you sell your CD changer to me (

), look on eBay or a junk yard for a BROKEN CD changer of the same design. Gut the guts and the face plate of the broken changer, and line the empty metal case with black felt. Because the metal case is already the right size, and already has the metal mounting tabs (being yours is a 2006) on the side, you can screw your now black empty perfectly fitting box right back in place. Voila, Instant cell phone and iPod holder. Reclaim your cup holder for cups!
In fact, you can do that you your own CD Changer this weekend and be good to go!
Disclaimer: I've never done it personally, so I cannot attest that it is possible. But you were looking for ideas, right?