This '69 440 Lynch Road built RR had a cast date of 5-1-69, an Engine Assembly Date (EAD) of 5-21 and a VIN 9A2706XX which might make it a last week of May/first week of June car assembly?
Another '69 "B" plant (Hmtrk) 440 has a 11-16-68 cast date with a 12-18 (or 2-18) EAD and a VIN 9B301XXX, maybe someone can chime in with an approximate car assembly date?
Another engine I have has a 2-27-69 cast date with a 3-28 EAD but no VIN (over the counter "crate engine"
)
It seems to be a 4+ week difference from cast date to Engine Assembly Date for the three 440 engines I have record of and maybe 2+ weeks from EAD to car assembly for two of them. I have seen blocks cast as much as 3-4 months from the EAD but not as many as the 4+ weeks cast to EAD and 2+ weeks into a car. That is my "ballpark" take but I'm sure there are many more with their own experiences to share. The A12 resto group was working on a K-frame date code as being a telltale on an approximate car assembly period but that's another
discussion IMO.
MikeR