The first post in this
https://www.largeformatphotography....to-look-for-information-on-LF-(mainly)-lenses discussion has a link to a list of links to sources of information that may interest LF photographers. It has links to sources of information on Horseman gear that I'm not sure you're aware of.
thanks. As for the Horseman/Topcor links there, I knew them. Was part of my homework before starting buying the gear. And they contain no data about the older lenses marked P.S. manufactured for the "Horseman Press" ie, Horseman 960, before the Horseman 970.
The older seem to come on a black board and after, still in older centimers designation, the P.S initials, but 970/980 style of hammered board and the cam color (red is for 90mm and 105mm):
it may be just cosmetic changes, or there may be differences in coating
here, on the left a Super Topcor 105mm "centimetric" (10,5cm), it is silver finish and bears P.S., on the right the most seen one, "millimetric" , black finish, no P.S. marking (and the board is wrong btw. green marking instead of red, but thatś not the point here...).
I was looking for the japanese catalogs. This one for instance is from 1979 and list schematics and specs for the common "millimetric" lenses. I try to find a similar source, that would be from early 1960's, with details of the "centimetric" lenses: