The person that has been collecting the data - how much data/years do you have or is this just a new project? Have you got a spreadsheet?
I have some random Canadian paint data (none of it is in one place) and it seems very year specific and numbers can even be used over again. Even the colour "names" can be different shades depending on the year - an obvious one is "Oshawa Blue" as the name has been used for a few shades of blue depending on the year. I've attached some Canadian 1941 codes that were sitting in front om on the coffee table. In this case the "1" could indeed indicate the year as being suggested.
I'd like to see this paint data slowly collected somewhere since it so different from the US colours and GM Canada Vintage Services no longer has this data due to the fire in the 80's.
I have pretty decent general data on Canadian models and engine numbers that was compiled by the late David Hayward. I've tried to circulate this over the years so might be common knowledge at this point.
