Engine casting numbers?

Hello, I found an old 455 engine for sale and am trying to find out what year it is.The block has been decked and I can't make out the stamp numbers between the plugs on the left side.Are there any good web sites that help identify casting numbers and such?
455 8 o No:
the cast number on this puppy is 1241735

 

Sure

http://www.buicks.net/shop/reference/bigblock_casting_numbers.html

That is a late :bglasses: 72-75 block.

 

thanks