Chevy Big Block Casting Numbers???

I'm trying to get as much information as possible from the casting numbers of a motor I just purchased without tearing into it. I plan to resell it and I want to know what I have. How specific can you get as far as the original application of the motor from block, head and manifold numbers and stamps? My motor's block casting number is 385591. My research tells me it could be either a two bolt 396 or a 4 bolt 427 built in '66. Anybody have any clues where to go for more info?

Try this link, it probably is a 396, but there are other things to look at like head casting and intake manifold numbers. 1968 was the first year for the spin on filter so that narrows it down too.

http://www.nastyz28.com/bbcmenu.html