lol!
I posted now because I never really got a definitive answer about the vented cover (at least, to me).
like:
was it a first series engine that they put into a second series?
or
was it a first series engine that someone swapped in.
or
did they still put the vented first series covers on second series engines in 1955
or
was the top part of the engine mated to a different bottom at some point?
or
etc.
right after that first post, winter hit here in the northeast and I did not work on the truck until recently.
I vaguely remembered posting about the vented cover and not getting a definitive answer, so I posted again.
I did forget finding that engine serial number (getting old...), and the breakdown someone provided (which did not make much sense to me at the time, and actually left me more confused than before - like: how could it be a 1957 engine with a vented cover that looked original, but vented covers were only used up to 1954, but it was in a 1955 and looked like it had always been in there?).
I have to say that going through the whole exercise again, and checking out the numbers on the engine (and sources of information like the gm heritage site which I did not know of until I fell over it), was a good experience for me (and might help someone else in the future?).
thanks to all for the replies and advice.
