So if you go by the CHEVY WAY for restoration than around three months before your build date, if you know the exact build date not the SPD. The CHEVY WAY that also is why people think a date code on a motor or block is good for a car with in a certain date or time before the SPD of a car. That is not the Chrysler way ONE motor came with every car and that is the original motor.

I would think date codes for tires and rims would be with in a mouth and a half before SPD baring any kind of delay from the manufacturer such as a strike or a transport accident. How much stock would Chrysler bring into the plant for storage back in 1970-71 and how much was used up per day. You also need to know how much FIFO was using back in the day First in First out.