Could someone out there with a November or December 1965, or January 1966 built original 1966 327 Nova please let me know what the casting # is on your engine block?
I have GM Canada paperwork on a '66 built 9 weeks after the documented engine code date. This would be the exception, but these kinds of things happened in the 60's.In my research I found the last 721 blocks were cast in October of 65 and the first casting of the 362 block was September of 65. One month overlap maybe to chase the flaws out.
I didn't think that the remainder of the 721 blocks lasted into January 66.