There is a machined pad just behind the distributor with a stamped number on it. The letter prefix at the beginning of the stamped number should identify the year of manufacture, and other details about that specific engine. There are several websites available with engine number decoding information, just google "Chevrolet engine numbers".
Jerry

EDIT: Try this link:
http://clubs.hemmings.com/clubsites/chevytalk/GMhistory/cast.html

Better re-check that casting number- - - -you might have a 261 engine instead of a 235. If so, that's a real find! The casting number you list differs one digit from either a 235 or a 261 number.
Jerry

Found it! The Inliners' site lists your casting number as a 60/61 truck 235.

http://www.inliners.org/becks/BCN2.html
Jerry




Last edited by Hotrod Lincoln; 02/02/2010 6:19 PM.
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