Amis,
I'm uploading the pictures of the XEGS that I'd like to swap for your 600XL with UAV installed. It's mostly a stock system. The ANTIC chip was socketed because we tried to put in a PAL ANTIC. Unfortunately, we couldn't find a monitor or TV that liked the PAL-60 format. I think the person that socketed the ANTIC chip also socketed another chip (MMU?) to make a future U1MB installation easier. I decided not to go that route with the XEGS.
I don't have the original packaging. The original owner probably threw it out back in the 1980s. However, it appears they kept the rest of the pieces intact. It has the original bundled games (Bug Hunt, Flight Simulator II), the matching joystick (upgraded by me to the Best Electronics PCB), the light gun (untested since I got the system in 2015 at a SCAT user group meeting - I don't own a CRT monitor to test it), XEGS manual for console and keyboard (the keyboard manual is pretty much a rudimentary intro to BASIC), 90-day warranty card and product registration card (they never sent it in to Atari), the Flight Simulator manuals and maps, and an ad to upgrade to the ST. I've never been an FS II fan, but I'll include that for completeness.
In the pictures, you'll notice that some of the keyboard keys are slightly discolored. I think the pictures show it well. I didn't feel comfortable trying any of the brightening treatments. Honestly, I think the XEGS had access to too much sunlight before I purchased a nice dust cover for it. I'll send the dust cover to you as well since I won't need it. The keys showed no discoloration when I received the XEGS in 2015. From the story I was told, it sounds like the XEGS ended up in an attic shortly after purchase. I've been impressed with how well it worked.
I did use it after I moved to Idaho. However, I'll need to set it up again and run Atariwriter to make sure all of the keys are still working.
Bop
600XL with 64K upgrade and UAV. BBSing on nitelite.ddns,net:9000