Do you have a broadcast sheet? If not you really don't know when you car was built... My Challenger has a Schedulde production date thats the same day my #s matching block was cast...The assembly date is three weeks after the cars SPD!! The acual built date was six weeks after the SPD, & even at that the "window" doesn't fit the above example...It really can be a wider spead, some times an engine got set toward the back & new stock of engines would bury it repeatedly, other times the engine was barely set down with the new shipment & it wound up in a car (Like mine) in 70 things were moving through the plants pretty steady, if you look at 68 however, there are plenty of cars that got engines 4-7 months predating the vehicle assembly date...
