There is a strong possibility that none came off the line in 1970. The new model introduction service bulletin for the Datsun 1200 I have is dated March 1970. So assuming that this bulletin would have been distributed very shortly before the models made there way into dealers, some 1200's would have already had to have been assembled. Prior to that the assembly line would have had some downtime to re-tool for a new model so thinking about it - it does seem unlikely they would have actually built them in 1970. They would most likely hav had enough stock from the 1969 production run to tide them over until the new model was available. sound reasonable?