I don't find much information on housing numbers or lettering on the center rear housing. Cleaning up my axle today and found the following marking.
Anyone know what the pink numbers should be? 1971 cuda, 383 AT, 3.23 suregrip. Build sheet says axle is D53. I wonder if the outer 2 markings are smudges???
Can't make heads or tails of the center markings, looks like an upside-down "2" in white, and a "J" in yellow.
https://moparconnectionmagazine.com/gallery-66-70-b-body-8-75-rear-differential-identifiers-markings/
Thanks Leo, I had seen that article too, but it didn't go into detail on what the markings represent.
I found the date code and ratio markings on my center section, but they don't match up with this chart. I had one white, one orange. Chart says I should have 3 black marks.