Chevrolet: ok my 302, block id, oil pan

Question
i was just wondering how you came up with 302? cause i am coming up with 327. was just wanting to be 100% sure of 302. is there a certain number that gave it away to you?   i pulled oil pan to run crank # it came back 307/327 it is a 2 bolt main. crank castings are (3941174) the other #s are all over this thang. what would help you on this mystery? i mean is it possible that someone put a 327 rotating asslembly in a 302 block? dont mean to bother you but im not a chevy expert at all. i mess with dodges mostly. i just dont know which other #S would be of help?....thanks alot brian

Answer
Brian ;
 Hi  well the engine  block id #s that are the ones stamped on it - on the right front of the engine block . the numbers you gave to me showed it as a 302 from a Z28.  re check the id # and I will re- check ok. also it is supposed to be a 4 bolt main. so I now wonder ???