Here is some artwork from a mid-60s commercial for Life Savers produced by Fred Mogubgub.
It's ink and marker on paper -not acetate. The paper is excellent, since the markers haven't bled much. There's very little bleed on the back.
There's also very little concern for title safety.
At some point Acme pegs took over from the Oxberry pegging. These are Oxberry. The distance between the pegs is the same, but the shape of the outside holes is different.
I wonder what precipitated this change. Is it only New York. Disney used a third system, like Acme, but three pegs span 7 inches opposed to 8 inches.
Only the middle woman is numbered. I haven't seen the commercial, but from this art I imagine it was mostly quick cuts in the style of "Enter Hamlet". The woman in the middle probably animated -that why she's numbered. The rest may have been held drawings.