230 or 250????

[72Lester]

Just blew the grease off of the motor in my '67 and ran the serial number off of the six cylinder's block and it came back as a Chevy/Olds 230 or 250 (Code 392168). Does anybody know of any ways to differentiate between the two? The head is stamped on the right side with 4883F15 and it does have angled plugs (if that makes a difference). It's not all that important to me but it could help me to get it running until I can find a small block to stuff in it. Thanks...