I just picked up my first Atari 7800 two weeks ago at a used game store. I added a S-video/composite mod, and hard wired the console buttons to arcade buttons via cat5 cable. All mods made for the arcade are reversible. I also ordered a new brushed aluminum decal and DB-9 to replaced the damaged one. The 7800 now looks good as new. It took the place of an Atari Flashback 2 with a harmony cart mod in my custom built arcade cabinet.
It has the Warner Communications Serial Number. Paddle games work. It lives in Vail, AZ.
The Atari 7800 Arcade Cabinet is a WIP. I'm designing the Marque, side graphics and monitor/control graphics. I'm exciter to get the xm and Harmony 2 cart in this cabinet.