8 3/4 Rear End Stamp ID - 7L27???

[CDN72SE]

Hi Guys,

Just doing some cleanup on my '72 318s rear-end, my question is what does the yellow "7L27" signify? I've read about the "489" case and the various coloured dabs but a search of the boards hasn't provided any answer. I'm not sure if I'm going to replicate it or not but I'm just curious as to it's meaning. I do not have a broadcast sheet... not sure if that would help things or not.

Any feedback would be greatly appreciated. When you've basically looked (and cleaned/replaced) at every piece of your car you start to get very, dare I say intimate with it.