BG220?

[MikeIIDC@domain.elided]

Sorry-  I posted this about two weeks ago and never saw any replies if
they came through.  My '63 T'all has a straight six cylinder engine.  On
the bottom of the oil pan, in fairly large numbers stamped into the pan,
is a "220."  In going to parts houses for occasional parts, I have seen
it listed in books as a "BG 220."  What does the BG stand for?  Anyone
know?  Is this indeed a 220 CI engine?  That is what I thought, but some
of the books are so confusing that they show "BG 220-241" or something.
Anyway, anyone that can enlighten me on this, please feel free.  I would
like to know everything about it that I can.  It has light blue paint
remnants on it-were these original?

Michael