Thank you MWilson, I will check that link out.Carling Contura II Series....the actuators are Western Star Truck but made by Carling...
Here is a little reading to get you started..https://www.carlingtech.com/sites/default/files/documents/V-Series-II-III_datasheet.pdf
They will snap in but are a whisker loose and can tip a little. That's why you see the Carling spacers in the unused holes. The center spacer had to be trimmed on the bandsaw a bit for a perfect fit...