John,
Try this web site to decipher your serial #. http://www.t137.com/registry/help/decode.php
Something isn't quite right with your number. First of all, it should start with an 8, and I think you have too many numbers.
1951 B3B serial #'s are 82215001 - 82256916 or 85308001 - 85313574
1952 B3B serial #'s are 82257601 - 82302000 or 85313701 - 85322000
As I recall, the "82" numbers were Detroit built, and the "85" numbers were built in California.
The serial # should be on a tag on the cab, driver's side door post, between the hinges. If that tag is missing, like mine is, you can find your serial # stamped into the left frame rail, just ahead of the front axle and behind the front spring mount. I borrowed this picture form the DPETCA site http://dodgepilothouseclub.org/index.htm , another great source of info on our trucks.
As for your engine #... If it is the original engine, it should start with T306, followed by a 5 or 6 digit serial number. This engine should be a 218 CID engine.
Welcome aboard.