340 #'s

The oil pan rail is where the VIN number will be unless the block has been replaced. Note that it is stamped and you may have to remove paint to find it. The number below the head on the driver's side will be stamped as well and the paint will have to be removed. Sometimes these numbers are stamped very lightly and are hard to read. This number will give you the year and the cid and a sequence number.

If they are not there, then you can't really determine anything other than you have a 340 block with a casting date of 7-10-69, which you already know. And you transmission is the numbers matching one (as I am sure you figured that out too).