Hi guys I'm new to the site. I have a manual steering box casting # 2537350-6. I believe 70/71. No other markings, cast any where on the box. NO circles with a year inside. On one of the covers is stamped D0715G. I presume an assembly date. From what I gather in other threads is the "D" indicates the year 68 the rest of the numbers don't make sense. Can anyone please help me understand mother mopar stamping system