1968 L34 exhaust manifold date codes

[My68SS]

Hi all, does the L1 7 code on this exhaust manifold decode to December 1st 1967?
Would that be a valid date code for a body build of 12C and an engine date code of 1204 [4th Dec]
Does the '178' number mean anything?
Casting - pn is 3916178
Cheers

[bertfam]

Yes, that date lines up nicely with your engine build. The 178 is just the last three digits of the entire casting number (located on the front). No real significance.

Ed

[My68SS]

Thanks Ed, this site has turned me into a numbers fanatic!! The car looked very original when I bought it back in about 1980 and so far the numbers I have found bear that out.
Would you believe back then neither myself or my friend that I bought the car off had any idea even about engine number matching vin number!!
It wasn't until another 6 or so years had passed that I discovered that fact by a chance comment being made at a motor trimmer where I had left the car for new carpet.
I immediately rang my friend to tell him about this number matching, he was shocked, raced outside to check the numbers on another camaro he had just bought and was over the moon to discover that they matched on his car as well!!

[My68SS]

Further pn research on exhaust manifolds has thrown up a question.
If the casting number [3916178] is the part number, then according to my p/a that number is for Chevelle 396
3919862 is listed for Camaro 396 [RH manifold]
Any comments on this appreciated.

btw, the missing pic has been noted in site comments.