Cliff Claven

I have a 4-speed muncie and where the date code should be I have the number 39116 and where the vin # should be I have a CC1 stamp.
I purchased it connected to a 396/375 from a 69 camaro, I haven't pulled the side cover off yet to verify that it is indeed a M22 as was indicated to me, but I can't find references to the strange date code numbers?
I also have an M20 which clearly shows the correct string of digits so it is not like I don't know what I am looking at...
I've exhausted myself and am now looking for help from a chevy guru!

Cliff Claven

First let me apoligize for the lack of info that I provided while asking for help... I know better.
I am 99% percent sure of this tranny being a Muncie, and wether it is a M20,21,22 is irrelavent, what I am puzzled by is the date code which is supposed to carry the letter P (for Muncie) in the string.
I have already narrowed it down by tailshaft number/spline counts/case code (3925661) and cover bolt arangement as a 1970 Muncie.
I have never seen another like it and am looking for enlightenment...
I am including more pics as well as a pic of my M20 date code so you can see what I mean.
Thanx to those who took a look.