In earlier years, Prestolites did have longer date codes. This 2444 853 is said to be 1965 Dodge/Plymouth 273hp 4 barrel auto and manual trans, stamped IBS-4013, date code 38 4, I guess week 38. If the 4 stands for 38th week of 1964, that would be September 14-20 week of 1964, which does not fit with October 1 being the start of a new model year? On the other hand, it could be that Prestolite did not exactly follow the auto makers' assembly line calendar, and the date code is, indeed, 38th week of 1964 headed for the October car assembly lines of the 1965 model year. Supposedly car makers wanted the new models to be available in the fall, because that's when farmers had their cash money annual income in hand, ready to buy a new car.