Which Space Commander is which?

Hello all, new guy here.

I run a website called History of the Button. Part of my research is in remote controls, which naturally drives me to the Zenith Space Commanders. In fact, I wrote a long post on Space Commands today.

I hope you can answer a question of mine. Long story is there. Here's the short story.

Zenith seems to have used the same Space Commander for years, but can you tell me in which years the following form factors were used? Thanks.

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