1972 350 engine identification

I recently began restoring a 1969 Jeep Wagoneer. I believe the engine is a 1972 buick 350. Can anyone tell me the differences between a '72 engine and the original '69 buick dauntless 350? I'm not sure where the engine serial # and product codes are on this engine. The airfilter housing has a 350-4 decal on it. Thanks for the help.