Those are cast iron bell housings in the last group of pictures. What year did they start using aluminum.

Those particular big blocks pictured just above are most likely BFT engines because of the bellhousings attached. The black exhaust manifolds are likely those found on BFT's and school busses too, and not a representation of what was used on normal passenger cars.

Those bellhousings look like truck applications?

I obtained and used those photos in the Assembly article.
The titles are with the pics. Specifically, the Life magazine pic is:
Engines As Received (at Tarrytown Assembly Plant, 1959)
http://www.camaros.org/assemblyprocess.shtml#engine

After looking at the 1970 dated Flint big block picture once more, the intake manifolds show dual thermostat upper outlet. Definitely BFT stuff.

Certainly a little on the manifolds here as well. Not so much on the bellhousing though. (from Kurts post/link above)

Cool picture, looks to be a protective “shipping cap” installed over the refrigerant ports on the A/C compressor.

Good pic of the Upper Balljoint. Appears to be natural (bare metal)

I don't know for a fact but believe that is done because they pre oil the compressor and add more and than apply a vacuum seal to it to keep all moisture out of it.

comparison- old - new
 

Pic of an early 67 Fremont Chevelle motor decked out like new one in factory pic.
Fremont pic?