Help decoding a rear

It would appear to be a 121st day of 69 rear. Have you checking the webbing for a foundry date?

Hopefully Dale will come back and possibly shed some light on the date stamps in the axle tubes. I originally thought it was a month / day / year thing....example the above mentioned CI 1219 B. But I did a little web search and found a reference on www.chevellestuff.com and seen it referenced as a 121 day of a year or as a julian date. Did this change for a certain model year as I believe in 67 they used the first mentioned example?

Thanks Dale I went back and re checked the web site. I was looking at the 71-72 rear axle tube examples and not 69 when they used a julian date type example?

James I to have read that before but have never compared. I believe that is why the say you will need to use the upper control arms to match the date of the rear.