Awesome pictures Robert:
You captured the spinning Kelvy perfectly.
Love the pictures of those two Super Rotoswirls. I'm guessing 1963 or 4 for the black, and 1968 for the gold. Now I know the black one was used until 1968 in 70 series models, all the way up to the 800 and also the 1963 and 4 LKs. The gold one with the scrubber is the one I question. I have only seen it in two models, both from 1968. The first is the model with the sliding control panel cover, and the other was a version of the model you grew up with. What other models may have had this?
Both are very shiny, and the scrubbers unworn; telltale signs they have never been used, or used very few times. Both are good to look at.
Have a good one,
James