You likely won't find a lot of information about them on the internet. Kenny Harman and Clifford Collins were from the southern California region. Harman split with the original company and just went strictly into camshaft work. Harman was in San Diego for a long time. I'm not sure about where Cliff Collins ended up but an engineer like him could go anywhere he wanted to. They started out in 1945 and had a shop at 5552 Alhambra Ave - Los Angeles, CA. Here are some snipits off the internet.
https://www.hotrod.com/articles/0602...parts-history/
https://www.jalopyjournal.com/forum/...ollins.227166/