Where are the serial number locations on a 340 block? Are they on the sealing surface of the pan rail? A fellow I know has a 340 I am looking to buy, he claims it is out of a 69 Dart but the date codes are 9 9 68. Very likely built in late 68 as a 69 model year. I wish to look up the serial number to help further identify the engine. 69 340 with x heads, stock intake and a .030 late 80's rebuild, still running for $1000 Canadian. Regardless of the dates I think thats a good deal. Another item to hold down my garage floor untill I find a home for it.