There seems to be a lot of discussions about bezel colors when referencing both the Heavy Sixer and Light Sixer. I have spent about a year researching this on the interwebs. combing through many discussion forums, and studying many photos and my own personal collection, I think I have finally have a answer.
The quick answer is.....every six switch made in Sunnyvale has more of a "Yellow" coloring on it's bezel, and every six switch made over seas has a more deep "Orange" color (like the Orange coloring of the 4 Switch consoles).
Most people are aware of the Heavy Sixer. The Heavy Sixer was first released in 1977, made in beautiful Sunnyvale CA. I would say 90% of the time, if you have a Sunnyvale H6er, then chances are the bezel coloring is more Yellowish then Orange. The reason for that is because that's the true color. It's not because it's "old faded orange" (I'll elaborate on that later).
What people might not know is, in 1978 Atari reached out overseas to continue production of the next variation of Atari (the Light Sixer). These were to be produced in Taiwan. However, in the spring of 78 Taiwan produced a limited number of Heavy Sixers before they completely switched over to Light Sixers. (Yes, there are H6ers out there that were made in Taiwan)
Those H6ers overseas were produced with the same dark "Orange" colored bezel that the overseas Light Sixers were.
(BOTTOM) Sunnyvale H6er with Yellow bezel plate
The color difference is also true for the CX-10 joysticks. Since most the H6er's were Sunnyvale, most of the CX-10 joysticks will be Yellow. The color of the joysticks were always made to match the Atari's faceplate bezel. This was also true for the H6er's built overseas.
.........the Light Sixer..........
By 1978 full production of the Light Sixer started up. Majority of the Light Sixers were produced in Hong Kong. Sunnyvale Light Sixers were also produced, however they didn't produce as many as the Hong Kong factories.
For the Light Sixers, the color variant continued. All Hong Kong produced Light Sixers were a deep Orange Color, While the Sunnyvale Light Sixers Maintained the Yellow tone.
Now of course I have found a few Atari's that don't quite match up with this theory. But it's been over 40 years and many consoles have not been kept in original condition, and many people have restored their Atari's sometimes altering the colors. But with my research, I have found this to be almost 95% accurate with every Atari I have owned and seen.