I have had very little time to work on this puzzle today, but this is what I have found so far.
With regard to CV, as I said before, I had two choices. Since it Was not the 8CV, it must be the 20CV.
With regard to type designation, So far I have only been able to determine three types. Specifically, Type R (1913-1916), Type V (1919-1924) and Type L (1925-1928). I have not been able to find other types, including something for the 1917-1918 period, but, because that period was during WWI, there may have been a gap in the production. I have been able to locate a photograph which more closely resembles the puzzle car than any photograph of the above type designations, but, unfortunately, this photograph has no type designation, only the caption "1913 Torpedo Speedster". Since I am not sure that a letter type is required, I will say the puzzle car type is a: "Torpedo Speedster". However if a letter type is required, based on the time frame of the discovered "Torpedo Speedster" photograph, I would guess that the puzzle car is a: Type R.