Did the seller happen to be named Barnum? According to this site, those numbers don't have anything to do with a 235 engine for a Corvette.

http://chevy.oldcarmanualproject.com/models/engine.htm

The casting number cross-references to a 1960 or 61 Chevy truck 235:

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

That block would be drilled for an oil gallery for hydraulic lifters, but you'd need to do a degree and lift check on the cam to determine if the cam is solid or hydraulic. A 1960-61 truck would have had a solid lifter cam from the factory.
Jerry



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