Help me with my date codes.

[Mr Cuda]

I have been digging out after moving,  and trying to sort and separate parts to sell.
I realized that I should try to put the parts back to cars , instead just selling the extras. 
So to that end, I'm starting with a bunch of trans crossmembers.
Once I figure out the pattern,  I can check the rest. Then move on to other parts.
For example mk-02-1
Or.     . mk-06-1, mk 43-1
But then they switch up with  191-14

[cuda hunter]

Is there any physical difference between the mk-06-1, mk 43-1 and the    191-14 ?

[anlauto]

Interesting, I never would have thought those parts were date coded....always figured those marks were just some vendor codes or lot numbers or something.....I'm now interested in learning more about this as well

[DeathProofCuda]

I've got MK-30-1.

70 Cuda built September 1969.  I've owned car since 1988.  Engine and trans are original and nearly all major date coded parts (minus the carb) are correct, so assuming this is the original trans cross member.

Will be interested to hear what you figure out.