1969 8 3/4 carrier date codes?

[69ISFINALLYMINE]

I know what to look for concerning part number cast into an 8 3/4 3rd member for a '69 charger, but are their any other codes stamped or cast into the carrier housing that identify the housing for my particular car?  I bought the car recently and the previous owner said that he swapped out the 3rd member for a 1970 sure-grip.  If I am going to start looking for a correct 8 3/4 3rd member to put away for a future restoration I would like to know if there is anything extra I should be looking at other than the casting number.
Thanks

[69CoronetRT]

Yes. There is a casting date in the housing.

[69ISFINALLYMINE]

Thanks.