What is the deal with this block??? He states 3 7/8 bore=283 not 327. I have read that these years can be bored to 4 inch, but the 327 crank throws can hit the bottom of the cylinders sometimes. This is where the 3791362 block was an update??? I don't know for sure.
And no, I don't think any 327 was offered in these cars in 64.