Somewhat depends on which engine, more to the point small or big block. As to dates, we need to know the date of manufacture of your car (door sticker, fender tag and/or broadcast sheet). That said, your engine and trans should be built not much more than several months before the car was built, many are within a month.
as to the location, again it depends on small or big block to a degree but the dates are cast into the side of the block.