I used a modified version of the standard Retr0bright recipe, since xanthan gum is apparently very expensive up here. I used an equal amount of guar gum instead. This left the mix far thicker than it should be. Next time I'll try about half the amount of guar gum. It may be much more absorbent than the xanthan.
Direct sunlight was used as a UV source, and since I had limited time it was only exposed for about two hours total. But just from that amount of time, the results are impressive.
In comparing the two photos, I was concerned the camera's colour correction may be pulling yellow from the after photo, making the end result seem more effective than in reality, but looking at the flooring, the warmer colours seem close enough. Also the space bar was quite different in colour to the other keys, and now in person it's a very close match to the other keys.
This is my first Apple II. I was in the Atari camp during the 8-bit days, so I look forward to learning a new platform.
I have the wee monochrome monitor for it, and may strip it down for treatment, too.