Atomarc, I think you are correct. If not, someone will be along shortly to let us know. Chevy info is all on that mortec website if you want to spend the time looking.
I just gave a quick scan of the website Fred T suggests. It is chock full of good info for the Olds engines.
ArticCat, go there and read up. It explains that the only difference between the Olds BB and SB was the deck height, and it explains how to tell the difference looking at your engine.
AMC used to do something similar. Their V8 was all the same block, whether the diplacement was 290, 304, 343, 260, 390 or 401. I think I read somewhere once that there are a couple different deck heights for Chev BBs too. Maybe that's the difference between the 366 and the 427 and 454.
