Alfred,
I did not compile the data, I found it on the internet, and of course we know, everything is factual on the internet....
Well, I did look high and low to find where I got that, but to no avail.
I have no reference for it, sorry about that.
I've had it for a few years and it regularly makes sense when I'm comparing the Becker serial numbers to the cars I am looking at when it appears all is original.
Sorry I couldn't be more specific.
Mark